Feb. 2 isn’t just Groundhog Day—it’s also Hromnice, the Czech equivalent steeped in folklore. The day marks the halfway point between winter and spring, once celebrated with candle blessings, noisy rituals to chase away winter spirits, and even knocking on oak trees to wake Perun, the Slavic god of thunder. Farmers also used it to predict the coming season, with the saying: “On Hromnice, about an hour more,” referring to the lengthening days.