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5.9 R, Trad, 3 pitches,  Avg: 3 from 142 votes
FA: Larry Hamilton, Dakers Gowans, 1974
Colorado > Boulder > Eldorado Canyon SP > W Ridge > W Ridge - part A - Ve…
Access Issue: Seasonal Closures Details


Allosaur is located near the bottom of the West Ridge in an area called The Amphitheater. To reach the start of the climb, hike a short ways up the West Ridge trail just pass the bouldering traverse. From there, scramble (4th/lower 5th class) up and right across some slabs to reach an area above the trail. Allosaur starts at a juniper tree at the base of a south-facing wall.

P1: move up and gradually left toward a fixed pin at 25 feet or so. From there, continue up and left across the face. The pro is runout and small (offset Aliens/RPs). The topo in the Eldo book calls this section .7s, but it may deserve .8s. The first 30 feet are fairly steep and continous. It ends at the band of purple broken rock, 80 feet.

P2: go up and right into an obvious, left-leaning corner protecting with small to mid-size cams. The 5.8 crux comes at end of corner. This pitch ends at ramp above the corner and below the next corner. The belay takes medium cams, 40 feet.

P3: go up and right again into left-leaning corner/roof protecting with small cams. The 5.9 crux comes near the end of the corner and is well-protected. This pitch is only about 40 feet and ends at the top of the ridge.

Rap rings are located about 10' to the west of the top of the route. Rap about 50 feet to a ledge and another set of rings then 100 feet (60m rope highly recommended) to end up about 20 feet left of the start of the climb.

Allosaur is fantastic. Just beware of the runout first pitch, although the rock is mostly solid and of good quality.


Cams up to a #2 Camalot. Offset Aliens and RPs are useful. Make sure to include small cams.

Photos [Hide ALL Photos]

Brad White mid-route.
[Hide Photo] Brad White mid-route.
Allosaur - the approximate line.
[Hide Photo] Allosaur - the approximate line.
Topping out.
[Hide Photo] Topping out.
Following the first pitch.<br>
Photo: Kevin Presley.
[Hide Photo] Following the first pitch. Photo: Kevin Presley.
On the first pitch about halfway up.
[Hide Photo] On the first pitch about halfway up.
Good fun on Allosaur, photo: Bob Horan.
[Hide Photo] Good fun on Allosaur, photo: Bob Horan.
Allosaur from across the creek.  Scramble in from the left and climb a 4th-class slot to access the route.  The belay at the end of the first pitch is on a sloping ramp; other options are to belay at the rappel tree on the left, or run the first two pitches together.  Two rappels to get off; a 60m rope is useful for the second rappel.
[Hide Photo] Allosaur from across the creek. Scramble in from the left and climb a 4th-class slot to access the route. The belay at the end of the first pitch is on a sloping ramp; other options are to belay…
Kevin Currigan just setting out on the first pitch.  Photo by Hill Slothower on October 29th 2003.
[Hide Photo] Kevin Currigan just setting out on the first pitch. Photo by Hill Slothower on October 29th 2003.
Peter Dillon at the crux step left on the last pitch of Allosaur.
[Hide Photo] Peter Dillon at the crux step left on the last pitch of Allosaur.
Peter Dillon turning the crux roof on the second pitch.
[Hide Photo] Peter Dillon turning the crux roof on the second pitch.
Approaching the roof on pitch 2 (done as a 3 pitch climb).  The crux on pitch 3 climbs out to the V notch at the far left of the skyline.
[Hide Photo] Approaching the roof on pitch 2 (done as a 3 pitch climb). The crux on pitch 3 climbs out to the V notch at the far left of the skyline.
The first pitch ...
[Hide Photo] The first pitch ...

Comments [Hide ALL Comments]

Tony B
Around Boulder, CO
  5.9 R
[Hide Comment] The route is super- you can link the first two pitches easily enough without super long slings. I had 3 two-footers. I ran out the bottom pitch quite a bit though, so perhaps if you are working in a lot of gear you will need more of those. The pro is not so good on the first pitch.

Furthermore, with a 60m rope and lots of slings, I have lead the route in a single pitch. You need a single set of nuts and a single set of cams, but doubles from 1.5-3" might be a good idea, at the most logical top belay would use those as well.

Most recently did the route comfortably in 2 pitches using a 50m rope. I went over the first roof and up above it to belay. The belay is on cams hand-fist. I would recommend taking a #3 Camalot or equiv. for the belay to set it higher than a #2 facilitates. Also, the initial traverse left under the roof will take a #2 or #3- so carry doubles or place before (1.5" cam) and after (small TCU) the hanging flake of the traverse to save your 2-3" pieces for the belay. For the next pitch (crux), the next roof takes great stoppers, tricams or TCUs.

I didn't see any need for offset Aliens or RPs, but then again, maybe I ran out those sections - YMMV.

When rapping on a 50m rope - the second rap ends on a ledge from which you can down-climb with a few 5.4 (?) moves. Jan 28, 2002
Chris Dawson
Grand Junction, CO
[Hide Comment] You're right Tony. I guess I got a little carried away with the offset Aliens. I love those things! You definitely do not need them on this route. They are merely useful... Jan 29, 2002
[Hide Comment] I've never found a better place in Eldo to use my off-set aliens!!! Thanx for the beta chris. Feb 13, 2002
[Hide Comment] Well described route onCB...but I would add: the route potentially is more than serious. That peg at 25'is a twisted out, 20+ year old upsidedown placed, soft iron mess. The dubious horizontal pro above and the moves to get to the mansize thank God flake certinly 5.8. Throw in the pull over the chockstone if doing 1st 2 pitches in 1, good 5.9. Pitch 3 has a crusty undercut flake for pro? good rock at crux. Not a 3Star. Apr 20, 2002
[Hide Comment] Did Allosaur today, you can combine the [first] 2 pitches no problem. I tried to do the whole route in one pitch with a 60m, which probably can be done, but was gettting some bad drag right before the crux on the "3rd pitch," so I just downclimbed and belayed in the corner. I used a quickdraw on the pin ,no slings, and got a small nut and TCU (clipped to draws) in before the roof. I'd agree that there might be an .8 move about 10-20 above the pin (a WWII army type pin, perhaps). Pro is not great on the first pitch, but there is always good feet and/or handholds. I [could]see where some small offset aliens would be nice on all the pitches. Enjoy! Jun 7, 2002
Brent Roaten
Anchorage, AK
[Hide Comment] This is a great route with adequate protection on the first pitch if you are creative. The entire route can easily be done as a single pitch with a 60m rope and carefully placed slings. Jan 14, 2003
Tony B
Around Boulder, CO
  5.9 R
[Hide Comment] As a person who considers himself pretty darn creative with gear I'd still say that there are potentially injurious run-outs on this route and that one should plan on having some significant lengths between gear, albeit on good holds.

I don't know Brent, nor do I know what he considers OK, so this is a "generic" comment, but I'd be suspicious of anybody's placements if they told me that they put in lots of good gear on this pitch. The placement and the rock both have to be good. That said, perhaps Brent climbed the line a little differently than I or my partners ever have, but most people think it merits at least a 'PG' rating. I was more than fine when I climbed it, but I also lead Territorial Integrity (5.10X) right next to it- which makes that no less run-out just because I was comfortable.

I'm not trying to quibble; I figure a difference of opinion is not always a bad thing- it can sometimes promote caution for those who might be in need of it. If I am wrong and off base, please explain how you protected this pitch so well? Jan 15, 2003
[Hide Comment] Why is this "Allosaur"? Well, from the road that looks like a set of gaping jaws you crawl into, on the upper part below the crux. The FA party imagined so, anyway. Feb 27, 2003
Shane Zentner
[Hide Comment] Very nice. Climbed this about a week and a half ago and enjoyed every pitch, especially the last. The first pitch is protectable though, as my buddy had adequate pro. I linked the last two pitches together which I would not recommmend because of rope drag. One of the nicest climbs on the West Ridge in my opinion. Jul 14, 2003
Scott Conner
Lyons, CO
[Hide Comment] Cool climb! I was able to get 8 points of protection on the first pitch (including the pin, which seems solid). Most placements were bomber and consisted of the blue Alien thru the .5 Camalot (purple) with a great #6 Stopper placement and a #3 Camalot near the top of the pitch. P1 seems fairly rated at 5.7 to me. An A-typical Eldo pitch where the holds face the way you want (up). You're mostly climbing on a series of small ledges...

We ran P2 and 3 together. Fun, bouldery climbing with good pro. A solid anchor can be built at the top with #1 thru #3.5 Camalots (or hexes). Sep 24, 2003
[Hide Comment] I just climbed [Allosaur] for the first time and, although I think it is a great route, I think the seriousness ratings (or lack thereof) for the first, second, and third pitches are fairly questionable.

The first pitch, in my mind, does not merit a serious rating. My partner placed gear at least every ten feet, if not closer, and the dubious, upward-driven pin at twenty feet can be backed up by a bomber piece just a few feet below. The crux section after this pin is only a couple of moves until bomber holds are reached. A few more moves and one can place a trucker cam behind a flake. The rest of the first pitch is awesome face climbing between diagonal shelves, with gear every ten feet or so. I have to agree with other writers when I say that, compared to other [Eldo] pitches of comparable difficulty that have an "s" rating, ie. upper [Grand Giraffe], [The Bulge], [Allosaur's] first pitch is not so serious.

On the other hand, I found the third pitch to be fairly serious unless one is climbing with a rack including nonstandard thin pro. I linked the second and third pitches together, which is fairly easy to do and eliminates the common [Eldo] phenomenon of the forty foot pitch. On the face climbing under the second roof, other than a bomber #3 Camalot down in the corner, my only pro was a #3 BD steel nut in a questionable flare until I reached a good flared jam near the end of the roof. I didn't find possibilities for pro in the seam underneath the roof, although I think a narrow-headed TCU, like an Alien, would go very well in a slot in the middle of the face traverse out the roof. This piece would be approximately the size of a yellow metolius TCU, I believe.

I am unsure of whether someone mentioned there being a fixed pin in the third pitch. If so, it is not in place anymore. I found the third pitch to be quite serious, with 5.9 moves 10-12 feet above a small wire I don't think would have held a long fall, and another 10 feet above a good cam in a low-angled corner that would have acted as a ledge in the event of a fall. Turning the corner of the roof is well-protected, the seriousness of this pitch is in the face traverse below the roof.

I urge anyone who found good pro in this pitch to write in and straighten this out. Perhaps, I was just having a bad day, or was trying to put a square peg in a round hole. Just don't want anyone to have a bad experience on a climb they thought was well-protected that isn't. Feb 17, 2004
[Hide Comment] You need Aliens for this climb? A #1 hex worked just fine. :-) Mar 21, 2004
[Hide Comment] We finally got to climb this route. What a treat!

I felt that the first pitch was run out but manageable, but I did not lead it.

We linked the second and third pitches with little rope drag, although I made sure I used a long sling to protect the start of the third pitch.

The run out at the beginning of the third pitch gave me some pause but the holds are positive and the rock is good. Great pro is to be found after a few feet.

I had been scared away from this climb for some time due to the S status. Now I am glad we did it.

WT Sep 21, 2004
George Bell
Boulder, CO
[Hide Comment] I felt the first pitch was somewhat runout, but it didn't seem too bad if you just keep your cool and don't get off route. I backed the pin up with a decent alien about 2 feet above and to the right. Up higher there are some runouts and the easiest line is not so obvious. If you belay on the big ledge off to the left, you almost have to go back down to get back on the (normal) second pitch. If you run pitches 1&2 together the third pitch must be only about 40' long! But perhaps this is the best way to do it. Sep 22, 2004
Ron Olsen
Boulder, CO
  5.9 PG13
[Hide Comment] Warren Teissier says: "The run out at the beginning of the third pitch gave me some pause but the holds are positive and the rock is good. Great pro is to be found after a few feet.."

The start of the third pitch can be protected by a couple of ball nuts in the seam under the roof, before the crack widens to Alien size. Sep 22, 2004
[Hide Comment] Can be done in one 60m stretcha Sep 23, 2004
Ernie Port
Boulder, Colorado
[Hide Comment] I led this today for the first time... in three [separate] pitches. IMO P1 is not [runout] if you have the right gear. Small cams sewed this up for me. It is steeper than I expected, but very enjoyable climbing. As mentioned by others, its a series of narrow ledges with very positive holds. A little runnout near the end of P1, but manageable.

P2 is a bit spicy getting up to the corner under the roof, and takes small/medium cams (#1) and a perfect (#3) camalot under the roof. Turning this roof felt like (8+), reminded me of the Tagger roof I did the day before...but not anywhere near that spicy.

IMO the last 30' are is [runout] at the start without ballnuts on your rack. Start by working out left, away from the roof, on nice corners and work back into the roof higher up where a perfect black alien placement will stare you in the face... in a flared crack on the face. Make one more move up and a yellow alien placement up in the seam of the roof is bomber... make one more move and place a blue alien again in the roof seam and send it to the corner, as the crack widens allowing you to sink your fingers in. It doesn't get much better than this... This route has great position and is one of the most fun routes of its grade I've been on in the canyon. Sep 26, 2004
[Hide Comment] FWIW, the original (FA) line on pitch 1 went more or less straight up, through the flakey depression in the center of the face (below the pitch 2 corner), instead of starting off right and then diagonalling to the left as marked on Ron Olsen's photo. I vaguely recall it was a bit runout, but on positive holds. Sep 27, 2004
Ernie Port
Boulder, Colorado
[Hide Comment] I went the way Larry describes.. pretty much right up the center, vearing slightly left to the corner of the belay ramp. But not as far left Ron has the dots going in his route photo. Positive holds the whole way... Sep 27, 2004
George Bell
Boulder, CO
[Hide Comment] I went the same way as Larry and Ernie! This seemed to me the easiest line (plus it is where the chalk seems to lead!). On the climb, it does not seem useful to go anywhere near the tree of the second rappel, since you would have to go right and down a ramp to get back on the route (as shown in the photo). I actually belayed at the right end of the sloping ramp, 40' directly below the roof on p2 (not a very comfortable belay stance). Sep 27, 2004
Ron Olsen
Boulder, CO
  5.9 PG13
[Hide Comment] The original beta photo I submitted shows an incorrect line on the first pitch; check the revised photo to see if it's more accurate.

The belay at the end of the first pitch is problematic; either belay from a poor stance on the ramp, or go all the way left to the rappel tree to a better stance. Belaying from the tree adds an exciting traverse to the start of the second pitch.

Perhaps it's better to run the first two pitches together. Sep 27, 2004
Ernie Port
Boulder, Colorado
[Hide Comment] Yes, that's the exact line I took on. Sep 27, 2004
Ron Olsen
Boulder, CO
  5.9 PG13
[Hide Comment] A note on logistics: I like to gear up at a spur on the West Ridge trail below some trees and take nothing extra to the base of the climb. The approach has a 4th-class slot at the end, and I don't like to down-climb the slot with a pack after the climb. If you have a 60m rope, the second rappel drops you below the slot, and from there it's an easy scramble back to your pack. Sep 29, 2004
[Hide Comment] The second rap with a 60m uses just about all of the rope so, as always, use caution. Great route! Jan 20, 2005
Chris Weber
Boulder, CO
[Hide Comment] I disagree with the earlier comment on the last pitch's gear options...I did this yesterday and was able to find excellent TCU and camalot placements the whole way. Fun route--combine with Morning Thunder for a great 3 pitch time. Mar 7, 2005
Mike McKinnon
Golden, CO
[Hide Comment] Great route! Only thing I would add is to run the 1st two pitches together. I belayed from the ledge and then got such bad rope drag from p2 I had to split it up into 3. The belay on the 2nd pitch is great so use it. I bet the whole route could be done in one long 70 meter pitch as well. Oct 17, 2005
[Hide Comment] Engaging route. A good mixture of crack climbing and face climbing. The lower pitch is classic eldo 5.7 runout, but has good gear behind the juggy flakes. Be aware of the chossy nature in areas. The upper pitch has nice cracks and corners for bomber gear. Mar 18, 2010
Phil Lauffen
Innsbruck, AT
[Hide Comment] Tim ran this whole route together with a 60m and prodigious use of slings. Great pitch. Oct 10, 2010
Keith Earley
Portland, OR
[Hide Comment] I for one found the second pitch to be harder than the third. P3 felt like 5.8 and P2 felt like 5.9. Also seconding a PG-13 rating on the first pitch. Even though upside-down cam placements behind flakes aren't the most confidence-inspiring pieces of pro, I think they would have held a fall. Feb 15, 2013
Ed Krejcik
Broomfield, CO
  5.9- R
[Hide Comment] Did this route today for the first time. I'd say this is a pretty soft 5.9. All pitches are really fun, and that first pitch is definitely R as far as I'm concerned. There's a fixed Alien at the first belay and a fixed C3 in the crux roof. Both are bottomed out, and we could not get them. Booty for someone.... Sep 26, 2014
Alex Vidal
Boulder, CO
  5.9 R
[Hide Comment] I don't find the first pitch run out to be too harrowing, it will take a smattering of marginal pieces which will likely keep you off the deck. However the beginning of the third pitch is frightening and potentially R rated with one piece between you and your belayer. Ballnuts potentially alleviate this problem. Apr 23, 2015
Golden, CO
[Hide Comment] I was able to place 13 pieces of gear on the first pitch. C3s, Peanuts, and Brass makes this route not run out. Gear up to 3" and bolted anchors are at the top of P1 and P3. One fixed stopper on pitch two. Oct 24, 2015
[Hide Comment] Pink Tricam placement to the right of the manky pin. Nov 22, 2015
J Thomson
[Hide Comment] This route is a quality moderate tour without the crowds. Recommend combining P1 and 2 to make for a more direct line (bolted rap anchor at top of 1 is 15' up and left, which makes starting P2 reversing that climbing down/right). Save a #1 and #2 for the belay at top of 2. Also, be comfortable running it out on the first pitch - most of the gear in the first 50'(small cams placed downwards behind flakes) is junk. Sep 3, 2016
Alexander K
The road
[Hide Comment] The climbing on the first pitch is easy, but even at 5.7, it only takes one broken hold for you to deck. There are a couple of bomber small cam placements on the 1st pitch. Also recommend linking P1 and P2, it makes for a cleaner and more aesthetic line. Oct 15, 2016
Carl Schaefer
Boulder, CO
[Hide Comment] I didn't find the first pitch to be run-out at all. The gear opportunities at any point aren't plentiful, but it can be sewn-up with mostly-standard gear (large stoppers and small/medium cams), plus a 0.1 x4 (up and right) to back up the pin, and a couple offset nuts & a cam. Stances are all good, so you can take your time and look around. Downclimbing the approach slabs afterwards seems more dangerous... :-)

[The fixed gear is all gone, btw.] Apr 13, 2017
Matt Hagny
  5.9- PG13
[Hide Comment] If the leader is paying attention, there's more than enough good gear on P1 as well as P2 & 3.

Very fun route! Aug 24, 2017
Keith W
  5.9 PG13
[Hide Comment] Fun, fun. The first pitch is great to get your lead head strong for the upper pitches. I also found the protection to be adequate throughout all pitches. PG-13 at most if you have the appropriate gear. I enjoyed the second pitch crux the most. The third pitch was a bit heady as I had a 000 as my only placement above the belay until I could get in some good pieces a little higher. Overall, it's a great route. Seems like the approach and R rating keeps a lot of people off of it. Get after it! Dec 4, 2017
[Hide Comment] I have to agree with Tony B. that the first pitch is easy (for a 5.9 leader) but had some dangerous runouts, especially considering the wasps. I'm sure pitch 1 and 2 can be combined, but I unknowingly combined 2 and 3, and that works too. In terms of wasps, by pitch 2, the wasp activity was decreasing substantially, and by pitch 3, I only saw about 10-15 wasps. Sep 27, 2018
Brighton, CO
  5.9 R
[Hide Comment] This route is great! It has everything you want in an Eldo outing. Good (mostly) rock quality, fun moves, spice, and a topout with as good a view as any in the park. Combined P1 and P2 and recommend climbing it that way. Be careful on the exposed scramble up to the route.

If you are a comfortable 5.9 leader in Eldo, the runouts on P1 should be OK. The pitch is a jug haul the whole way. Personally, I thought the first half of P3 was the worst runout of the route. Maybe I missed something, but there wasn't much there for gear/ I did get a horizontal #9 BD nut in on that part, but it was probably not bomber. The crux of P3 is well-protected, however.

The roof at the top of P2 (5.8+ in the new guidebook) felt harder to me than the P3 crux, but maybe that was because it was the last move of a long combined pitch. The P3 crux is more of a balance move. Nov 10, 2018