For more than a decade, the McCormick Tribune Ice Rink has cultivated an open-air expanse of ice between the skyscrapers of Michigan Avenue and the twinkling walkways of Millennium Park. Open seven days a week, the rink generally stays frozen from mid-November until mid-March with the help of a high-tech refrigeration system. Admission is free, allowing those with their own skates to hit the ice without delay, and rentals let visitors lace up within minutes. After taking off their skates, guests can practice learning how to walk on land again by ambling across the plaza to the Park Café for hot chocolate and snacks.