There are 2 actually. The quad serves blacks Challenge and Thunderbolt. The one to the west (double triple) allows easy access to Thunderbolt, but you have to skate a little to get to Challenge. Plus you had to deal with the park rats :-). From both of these trails you can’t return to that lift (which normally serves blues) but have to go over to the East mountain lift. From that lift you can of course ski East mountain, but you have to do a fairly long downhill traverse to Challenge, or do the traverse and skate a little to get to Thunderbolt. Thunderbolt was pretty deserted all last year. It wasn’t too bad to lap Challenge on the East mountain chair, but thunderbolt was a pain. Hard to get a rhythm, and for me at Frost with the slow lifts, it is all about hopping off the lift and being right at the top of the trail, and then skiing right onto the lift without any traverses. Although the bottom of East mountain is a pain with the flat runout. Plus the East mountain lift is 90 seconds longer than the quad for really no increase in skiable elevation. Doesn’t sound like much, but when you do 20 trips in a morning, it adds up. The quad is 6 minutes up, 90 seconds down.