Just thought I would add this in:
From I35 Austin area: South on Interstate 35 to San Marcos. Take HWY 123/Seguin exit and go east to Seguin. Take Interstate 10 South (right) to Marion, the track is on the west side of the Interstate and you can't miss it.
From San Antonio area: take Interstate 10 toward Houston. The track will be on your left near the town of Marion. Can't miss it!
See you there.
DW