Are there reservations? What insures that you get more than 2 trips down the snow in the hour?

Yes you can Reservations, and Snow Tubing is $21.99+Tax for and Hour. For$26.99+Tax you get an Hour of snow tubing+30minutes to play in the snow pit. Over all you'll leave having an awesome Tubular Time@Pigeon Forge Snow!!!

I'm not sure about reservations. luckily we went at night so there weren't a whole lot of people and we got to really take advantage of the full hour, but we asked them that and they said when it is super busy, they try to get 6 rides in per person.