The Linda Vista Loop Trail is fairly short at only 2.5 miles, but it's a fun, challenging singletrack trail right off of Oracle Road. There's decent parking at the trailhead and signage showing you the layout of the trails.
If you're headed in the clockwise direction you'll begin ascending pretty much immediately and go up just over 450 feet, almost all of which is in the first half of the trail. It's also a relatively narrow trail with quite a few tight turns and pretty rocky in most spots. Your outing can be lengthened by doing multiple loops, adding on road miles before/after the trail, or there's also another trail that bisects this loop which can also be added in.
While not really a destination trail, the Linda Visa Loop Trail can be used to break up your normal routine or as a convenient shorter option for those living close to the area. You'll find other visitors along the path often as the route is reasonably popular for guests of the nearby Hilton El Conquistador.