Matthews-Winters Park 

I checked this area out recently and just wanted to add something to make it clearer:

When approaching the boulders from the red rocks trail, follow the trail to the split and then go right.

I took the trail to the left and got turned around for 15-20 minutes.

-cheers-

Yeah Scarecrow, the directions are a little confusing on the main Millennium Boulder description as they are from the I-70 entrance, which I suggest everyone avoids as it takes a lot longer.

In the comments on the Millennium Boulder is a better description on how to get to the main boulders from the Red Rocks Entrance #1:

"From the parking lot, one can cross the road and take the RR trail into Jeffco (Matthews/Winters). After a series of switchbacks along a beautiful red wall, a fork occurs. Either continue up and have a nice hike, or take the trail right, below the ridge. After about 1/2 mile you will see the MB downhill on the right. Keep going past it till you find the trail. Watch for cacti, snakes, slumbering elk, and prarie dog holes."