An acre-sized ice castle is now open again in New Hampshire.
The Lincoln castle - one of four in the country - features archways, tunnels, an ice slide and glacial waterfalls that are lit up at night. Last year's version was at the base of Loon Mountain. This year, the Utah-based Ice Castles entertainment company chose a location next to the Hobo and Winnipesaukee Scenic Railroads.
The construction process involves elaborate sprinkler systems that spray water onto metal racks to produce thousands of icicles. The icicles are then harvested and stuck to the ground around sprinkler heads, where they are drenched in water and grow in various shapes and formations depending on the temperature and wind.
Other castles are opening at Vermont's Stratton Mountain and in Utah and Minnesota.