This is a simple loop. 3 miles up the dirt road to Baker Tank. Turn left onto the singletrack and follow it three miles back to the parking lot. The grade of the gravel road is very slight and the only really steep part will be at the beginning of the singletrack. After that, it's mostly level and roller coaster before dropping sharply back to the start. The singletrack portion is well covered and at altitude, so it usually doesn't dry out until mid-late June. It is also very rooty, demanding caution when wet.
From downtown Breckenridge, head south on Highway 9. Turn left on Boreas Pass Road. Drive 3.5 miles to the Winter Trailhead (just after the road turns to dirt).
http://www.singletracks.com/item.php?c=1&i=6838