OKC RIVERSPORT’s RUNderground 5k is one of Oklahoma City’s unique competitive running experiences. As part of the annual Bart & Nadia Sports Experience, RUNderground takes participants through downtown OKC’s underground tunnels. The race starts and ends on the first floor of the Cox Convention Center. The 2014 RUNderground 5k will take place on Saturday, Feb. 22 at 12p.