Folks, this is NOT a mountain bike trail. I added it to the site because I had several requests for it. I don't ride BMX so I don't know how this stacks up with other trails. The signage specifically states "no mountain bikes" so I'd make sure that if you are riding it that you are on a BMX bike just to stay out of trouble.
The track is actually sanctioned by the city; if you ride BMX I recommend getting involved with any track building efforts in order to keep it going. Based on potential liability for the city there is probably someone willing to try to shut it down - activism goes a long way towards keeping it running.
Location: Central Austin, West of downtown
Directions: On 9th street about a block east of Lamar, just past the Shoal Creek Greenbelt. If you are riding on the greenbelt there is an entrance just under the 9th street bridge, bear east instead of west.
Technical Level: Can't say, I don't ride BMX