Those bumps make you appreciate the straight, smooth trails even more.
But the road recovered when Albert Pope, wanting smoother trails for his Columbia bicycles, led a movement for state-of-the-art paving.
With most trails in the forest preserve now serving hikers and sledders alike, environmentalists worry that the new plan would turn many trails into de facto roads, noting that it calls for large groomers with treads akin to those on tractors or armored vehicles to smooth certain trails.
With the invention of the motor car, snow groomers were replaced by snowplows and snow blowers on public thoroughfares, but remained in use at ski resorts, where they are used to maintain smooth, safe trails for various wintersports, including skiing, snowboarding and snowmobiling.
Any designated cross country skiing area should have smooth, groomed trails, often with two tracks to slot your skis into.
To ease the difficulty of mass production, the leading edge of the wing was straightened out and the ailerons' two aerofoil sections had smooth leading and trailing edges.
The group said the trail is smooth and wide enough for people in wheelchairs.
Generally ridden March through November, the trail is smooth and fast, and the scenery — a wonderland of cliffs, mesas, stratified hillsides, wind-combed prairie, river canyons and bentonite buttes — can be surreal.
"PC sales rarely trail a smooth curve throughout the year and I think at this point there is very little visibility going forward," he adds.
