Underpass is a sleepy mining town that derives its name from the foundation project of building a mine that would provide a tunnel through the mountain pass, subject to municipal tolls for adventurers and traders. However, the project was quickly scrapped as the demand for bulk iron increased in New Caledonia.

Although changing the town's name was discussed, local business owners feared this would drive away the clueless adventurers and traders that showed up expecting easy access to the western island.