The trails vary from rocky to...well rocky. The trails are very fast but we share most of them with joggers. The upper loop is very fast and has some cool views of the airport. There are bathroom facilities available and several pavilions for BBQs and the like. On Saturdays there are a multitude of activities out here from soccer games to running events. the local bike clubs have races out here every year as well. The fee is FREE and the park is a good place to bring young or inexperienced riders. There are some pretty good hills to try their legs out on as well as some VERY rocky areas to try their suspensions out on as well (THE ROCK GARDEN). Overall this is a pretty good ride for a quick 10 miler!
From San Antonio, TX: From Loop 410, drive 3.2 miles on U.S. Highway 281 to Bitters Road. Turn east on Bitters Road to the junction with Starcrest, then continue on Starcrest until Jones-Maltsberger Road; turn left on to Jones-Maltsberger and proceed 1 mile to the park entrance on the right at 13102 Jones-Maltsberger. There is a MAPQUEST map link (on the web page) if you need better directions to the park.
http://www.singletracks.com/item.php?c=1&i=1487