This is the park's star attraction and the world's highest continuous paved highway, topping out at 12,183 feet. The 48-mile road connects the park's gateways of Estes Park and Grand Lake. The views around each bend—of moraines and glaciers, and craggy hills framing emerald meadows carpeted with columbine and Indian paintbrush—are truly awesome. As it passes through three ecosystems—montane, subalpine, and arctic tundra—the road climbs 4,300 feet in elevation. As you drive the road, take your time at the numerous turnouts to gaze over the verdant valleys, brushed with yellowing aspen in fall, that slope between the glacier-etched granite peaks. Rainbow Curve affords views of nine separate mountain peaks, each more than 10,000 feet high, and of the Alluvial Fan, a 42-acre swath of rocks and boulders (some the size of cars) left behind after an earthen dam broke in 1982. You can complete a one-way trip across the park on Trail Ridge Road in two hours, but it's best to give yourself three or four hours to allow for leisurely breaks at the overlooks. Note that the middle part of the road closes with the first big snow (typically by mid-October) and most often reopens around Memorial Day, though you can still drive up about 10 miles from the west and 8 miles from the east.