“A tough, unforgiving couple of climbs and descents packed into 3 miles.
— Phil Lucero
This trail's name is misleading, as in there are not many "viejo's" that could get through it, but perhaps the name refers to how long it's been around.
It's a great, lightly-trafficked trail that is deep in the Santa Fe National Forest. This is an unforgiving trail that is usually ridden as a return from the larger Borrego / Rio Nambe ride (though it might be slightly easier going the opposite direction as the initial climb is extremely steep and might be a better descent).
The trail climbs two ridges before ultimately making its way down the the Rio En Medio Valley. Here you can hook up with the Rio En Medio trail or hook up with the Double Discount Trail (on the left after a brief stint on Rio En Medio going west) to go toward Pacheco Canyon road.
It's a fun trail, but come prepared to work. If you are heading northeast on this trail, you have the option of continuing on in the same direction to do the newly-cleared Rancho Viejo loop (or triangle) or turn east to climb Rio Nambe and return on Borrego. Those would be a HUGE days.