O-9 Well

Preserve Manager: Bennett Lee

O-9 Well is a classic Texas cave. It is a multi-drop, 100-meter-deep cave that requires a wetsuit and proficiency on rope. The cave is historically significant, once serving as a stop on the Ozona-San Angelo stagecoach line and during cattle drives between Mexico and Kansas City. A windmill is still used to draw water from the cave today.



O-9 Well is managed by TCMA for the University Lands System. Per our management agreement, only TCMA members may visit O-9 Well for management or research-related trips, although recreational trips can take place before or afterwards. Access requires a formal request process, and thus, you should contact the cave manager well in advance of any proposed trips.

If you are on an approved trip and need to become a TCMA member or renew your membership, you can do so online on our Membership page. With your membership, you will receive a confirmation email that you must submit to your trip leader before entering the cave.

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