From the Canadian border to outside of Dawson City, Yukon Territory, Canada, The Top of The World Highway is mostly dirt but I would call it gravel because significant portions of it are gravel. East of the Canadian border for maybe 20 miles is pretty marbly gravel that motorcycles should use caution on. There are other shorter spots with this type of gravel that exist throughout this route. The road starts at the top of the mountains and follows the ridge lines of these mountains for almost the whole way to Dawson city. It’s spectacularly beautiful. You get to see the whole area from up high, sometimes above the tree line. There are no services on this road till Chicken, Alaska so gas up in Dawson city and then gas up and Chicken or Eagle, depending where you’re going. In summer, the road is fairly well traveled for being so remote, because it is a popular road destination for travelers. There is no cell service, at least when I was on it.