When it’s cold out, some people want to escape to warmer locations. But hundreds of thousands of people head to Northeast China to revel in the cold . . . or, at least, a cold-weather spectacle.

The 35th Harbin International Ice and Snow Sculpture Festival, which officially opens Saturday, invites visitors to walk in and around hundreds of ice castles and monuments lit up in rainbow colors — while temperatures at night often drop below zero.

The structures, which take thousands of workers several weeks to build, are made of ice blocks cut from the city’s Songhua River.

This chilly celebration started as the Ice Lantern Garden Party, during which local artists displayed lanterns out of hollowed-out ice blocks. The party now lasts two months — unless an early spring turns the sculptures into slush.