While temperatures hovered about the zero mark early Tuesday morning, two intrepid campers wre trying out their new snow cave in front of their house, at 1420 Sigsbee Ave. in Salt Lake City.

Richard Lee, 21, a senior at the University of Utah studying physics and his sister, Katherine, 14, a ninth grader at West High School, spend Monday night inside their frozen dwelling "to test their winter camping abilities," Richard said.

The two took advantage of the huge snowfall Sunday to build up an eight-foot-tall pile of snow beside the street in front of their house. Then Monday, they carved out a cave inside the snow pile. Monday night, they put two blankets on the bottom of the cave, crawled in with their sleeping bags and a flashlight and went to bed.

Richard said he wore only his underwear. Katherine said she kept her clothes on and a jacket. "I was cold, too," she said. "I did sleep, but I woke up several times because of the cold. I wasn't particularly comfortable," she said.

Her brother said he slept pretty well. "I'm used to camping. I'm planning to do some camping in the snow near Park City this winter and this was practice." he said.

Both Lees said they don't plan to sleep in their snow cave again and they have not been able to interest their sisters, Patricia, 19, or Sandra, 24, nor their parents, Carol and Benjamin Lee, in sleeping in the cave. But, they said, a married neighbor has indicated he might want to try it some night soon.