Allowing 256 x 256 100 MHz RF channel emulations, with USRP X310 radio nodes in the loop interacting in over 65,000+ channels at the same time, Colosseum can create virtual worlds, as if the radios are operating in an open field, urban area, shopping mall, or a desert, by generating more than 52 terabytes of data per second. Colosseum enables full-stack wireless networking research from applications down to the physical layer at scale - with up to 256 interacting radios.