Enjoy Austin as you cruise around the lake and Zilker Park, then cool off at Barton Springs Pool. Two way loop with plenty of ways to lengthen or shorten the ride. Lots of local food and even a few live music venues within earshot. Can be extremely crowded in the morning.
From IH 35, take Riverside Drive heading west till you dead end into Zachary Scott Theater. Park and jump on the trail.
http://www.singletracks.com/item.php?c=1&i=2174