A frost fair was a celebration held on the surface of the River Thames when it froze over. Carnival festivities, shows, games, ice skating, shopping and other celebratory events were held on the open surface of the ice. The Second Doctor, Jamie McCrimmon, Ben Jackson and Polly Wright visited one such fair in 1648. (PROSE: The Roundheads) In February 1814, the Hyban Masoon came to Earth and froze the Thames, starting the frost fair. The Tenth Doctor also took Mai Kondo ice skating at this time. (WC: The Frozen)