Elon Musk’s craziest project is about to become real by Benjamin Snyder @FortuneMagazine February 26, 2015, 2:12 PM EDT E-mail Tweet Facebook Google Plus Linkedin Share icons Elon Musk’s futuristic Hyperloop tube-based transit system is getting a lot closer to happening. A company called Hyperloop Transportation Technologies says it’s ready to build a five-mile prototype track for the Hyperloop system first proposed by Musk in a 2013 paper. HTT plans to build the track in California’s Quay Valley for an estimated $100 million, according to CNBC. The prototype Hyperloop track won’t have the distance or supersonic speeds Musk originally desired, though. “It’s not a test track,” HTT CEO Dirk Ahlborn told Wired of the Hyperloop project. “Speed is not really what we want to test here.” Hyperloop Transportation Technologies isn’t the only group working on a Hyperloop prototype: Musk himself tweeted last month he’s working on a test track “most likely in Texas.” Will be building a Hyperloop test track for companies and student teams to test out their pods. Most likely in Texas. — Elon Musk (@elonmusk) January 15, 2015 The Hyperloop is a theoretical system in which passenger-carrying vessels would blast through low-pressure tubes at ultra-high speeds with the help of induction motors and air compressors.