Hundreds of spectators crowded the slopes of Jack Frost Mountain on Friday for the fifth annual Cardboard Classic, hosted by Preston and Steve of 93.3 WMMR in Philadelphia, with some arriving as early as 6 a.m. to claim a prime vantage point to watch the event.

Close to 200 listeners from all over the Philadelphia region, and as far away as Delaware and South Jersey, designed and built cardboard sleds, with some as large as full-sized buses, to be raced down the tubing hills at the area ski resort.

The rules state that all sleds must be made of nothing more than cardboard, string, duct tape, paint and paper.

Prizes were awarded for creativity and design.