At confluence of Onion and Williamson creeks with quiet pools, occasional rapids and waterfalls. Excellent visitor center, hiking and interpretive trails, campsites, playground, ruins of homestead of Thomas F. McKinney, one of Stephen F. Austin's original 300 colonists. Situated about 13 miles southeast of downtown: From U.S. 183 south, take Scenic Loop Rd. west to park entrance. Admission fee. Call 800/792-1112 or 512/243-1643.