Player Embed Code: <iframe width='500' height='300' scrolling='no' frameborder='0' style='border: none; overflow: hidden; width: 500px; height: 300px;' allowtransparency='true' src='https://www.dvidshub.net/video/embed/814723'></iframe> Download Embed Share DARPA Kicks Off Subterranean Challenge Final Event War.gov Sept. 21, 2021 | 37:08 The Defense Advanced Research Projects Agency hosts the Subterranean Challenge event in Louisville, Ky. Teams compete in systems and/or virtual competitions. They must compete in three circuit events that explore the difficulties of operating in specific underground environments.