[4] In 1976, while studying engineering at the University of Texas at Austin, Stone took part in an expedition to the Sistema Huautla in Oaxaca, Mexico, where his group set a new penetration depth record of 2,624 feet (800 m).
[5][6] From 1998 to 1999, Stone directed an international group of explorers consisting of over 100 volunteers to participate in the Wakulla 2 Project.
[7] Stone was the principal investigator for the NASA-funded DEPTHX project, which produced a highly advanced AUV to explore the world's deepest sinkholes.
Both projects served as a testing ground for developing a vehicle that can autonomously scour the seas of Jupiter's moon Europa for signs of microbial life.
[12][13][14] Bill Stone gave a talk at TED 2007 about exploring the world's deepest caves and frontier space travel.