San Carlos Trail is a 3.4 mile lightly trafficked out and back trail located near Rye, Colorado that offers the chance to see wildlife and is rated as moderate. The trail is primarily used for hiking, walking, and trail running and is accessible year-round.
From the gate on Robb Road, it is a 3.2 mile hike one way to the trailhead according to my GPS. The road was still closed as of 4/7/16, but even when open, it is definitely only passable by jeeps and ATVs in its current condition. Pretty trail, but unless the forest road is open and you have a jeep, be ready for the 6.4 mile round trip approach.
Hiked this with my daughter and son-in-law in October. We chose to follow the river and not the "trail'. Awesome hike with many river crossings and some bushwhacking. Because of just a tight group of hikers and laughter one of the best hikes ever. Because of the bushwhacking, it probably seemed a longer hike, but would do it again in a heartbeat. The arch at the end is awesome. The high canyon walls, moss, fungi, and just total canyon experience of a rarely traveled trail is worth a weekend. And an awesome memory for the future...