The main rail route from Denver to points west used to crawl up numerous curves and trestles over nearby Rollins Pass. Now it takes a more direct route under the Continental Divide via the six mile long Moffat Tunnel. Thanks to this train track, hiker, skiers and climbers have good four-season access to a trailhead deep in the mountains. And they say technology hasn't brought us anything!
The East Portal Trailhead serves the very popular South Boulder Creek Trail. Five miles of hiking on good, well-marked trail brings you to the picturesque Heart Lake nestled under the Divide. Four other cirques and attendant lakes are accessed off this trail, some with good trails of their own, others with some impressive bushwhacking.
Looking back down the South Boulder Creek watershed to East Portal.
On the Peak to Peak Highway (CO 119), drive to the small village of Rollinsville about four miles south of Nederland. Head west from the center of town on the well-marked Rollins Pass Road. The road is dirt, but is wide and in good condition. The road is plowed all the way to the tunnel and even low-clearance passenger cars should have no difficulty in any season. Follow the road 8 miles crossing the active train tracks twice via at-grade crossings and twice via underpasses. After the fourth crossing, bear left at the junction for Rollins Pass and continue another half mile to the large trailhead.
This is a very cold and active area with large railroad machinery and a number of tunnel-related houses. The old trail crossed the tracks and a bridge, however this has now been closed off with a gate. The new trail stays north of the tracks and goes around the tunnel head. Look for signs at the west end of the parking area.