It runs northeast into the town of Los Alamos, where it ends.

Guard posts are at either end of the LANL section of the highway, and motorists passing into (but not out of) LANL territory must pause at the posts and be waved through.

Under most conditions, no inspections, etc., are performed at the guard posts, but heightened security postures at LANL may lead to more intrusive checks.

NM 501 is part of the Jemez Mountain Trail National Scenic Byway.

The entire route is in Los Alamos County.