Greater Hsouton Grotto was activated on November 28, 1972 as a Grotto of the National Speleological Society. Grotto members regularly participated in TSA function, and were extremely active in northern Mexico caving. Members were responsible for the earlist recoinessance trips into the Purification and Portero Redondo caving regions of Mexicoin early 1970s, and discovered and explored both Cueva del Brinco and Cueva de Infernillo - later to be connected to form The Purification System, the longest air-filled cave in Mexico.
During the 1990s, emphasis increasingly shifted to the Guadalupe Mountains of New Mexico.
The Greater Houston Grotto is the fourth longest-lived caving group in the state, following the UT, Dallas-Ft. Worth, and North Texas Speleological Society grottos.
(From Carl E Kunath, 2007 - 50 Years of Texas Caving)