San Marcos Springs (Texas)

San Marcos Springs, the second largest natural cluster of springs in Texas, is two miles northeast of the county courthouse in San Marcos in southeastern Hays County (at 29°53' N, 97°56' W). The springs were originally called Canocanayesatetlo (meaning "warm water," although the water is only slightly warm) by the Tonkawa Indians; they have also been known as St. Mark's Spring and recently as Aquarena Springs.qv The springs' artesian flow issues from the Edwards and associated limestones in three large fissures and some 200 smaller openings along the Balcones fault zone, thus forming Spring Lake and the San Marcos River.
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