If you are going to ride Purgatory Creek - San Marcos then you have to ride Prospect park, which is technically another trail, but is actully interconnected. It is shorter than Purgatory but it adds some total mileage to the ride. The trials are obviously close to Purgatory in their makeup, but a little more tame, less climbing, fewer rocks.
There were several runners and hikers out, Prospect is a more likely destination for those types, even though Purgatory has a GCW nesting site that is closed from March 1st through late summer or so (we rode it on March 1st of course.)
Location: San Marcos, TX
Directions: Take I-35 south and get off on Route 12 that takes you through the middle of town. You'll head less than a mile west on 12 and you'll hit Hunter. Take a left on Hunter and the parking lot is right past the intersection. From the trail head you'll go under 12 on the trail to get to Prospect Park.
Technical Level: Low
Length: About 2-3 miles
Trails: A wide variety of trails, some smooth, some rocky. Very little elevation. There was one tree/rock feature that was cool but the rest was pretty vanilla
Trail Map: City trail map
Shade: Very shady
GPS Map: GPS map
Post-ride Beer: Zelicks is right up the road. We rode up there to get a beer, and unfortunately they didn't open until 3
Links: City web site