Really nice park. There was an issue last year, but they have widened many of the trails to reduce undergrowth and improve sight lines along the trail. They are also improving some of the paved trails.
Personally, there is so much more to the trails than just what is paved. Even the official map found here: http://www.sanantonio.gov/parksandrec/pdfs/OPSchnabel_map.pdf doesn't show all of the trails. I have used a mix of dirt and paved trails to get in a nice 5+ mile walk/hike.
In addition on every walk that I've taken, I have seen a variety of birds and at least two deer. So this park is also a haven for wildlife.
Getting off the trails, there are a number of picnic areas (two of which are quite large and covered) a nicely redone play area with a rubberized surface, a little water area to help beat the heat that is attached to the YMCA that is in the park.
The sports fields, soccer and baseball, all are very nice and can get crowded on Saturdays, so plan accordingly.
Overall, it is a great place to get away from the hustle and bustle of the city, which, in my opinion, is the purpose of a park.
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