The South Boundary Trail is, by far, one of the best mountain biking trails in all of New Mexico. Famed for its epic downhill, this trail is not to be missed. The entire ride runs through beautiful mixed coniferous forest and open grassy meadows. The steepest climb will hit you within the first 2 miles, after that it is smooth sailing. You may want to stop and take a break around the 13.5 mile mark, before you hit the technical descent you've so long been hearing about. You will want to set up a shuttle for the ride, or call one of the local bike shops in Taos - many will shuttle you for a fee.