The Great Allegheny Passage (GAP) bicycle trip

The Great Allegheny Passage rail-trail offers 150 miles of hiking and biking between Cumberland, Md., and Pittsburgh.

The GAP trail has a packed, crushed limestone surface for a smooth ride. Built mainly on abandoned rail beds, the trail is nearly level, with an average grade of less than 1%.

The GAP gets more than 750,000 visits between April and November.

The Western Maryland Scenic Railroad pulls into the station in Frostburg, Md.

A sculpture of a bike and rider at the trailhead in Frostburg, Md.

The trail takes riders across six soaring bridges and through four mountain tunnels.

The Gingerbread House Bed and Breakfast in Rockwood Pa. The Allegheny Mountains are rich in fall color. Options range from self-contained independent rides, in which riders tote their own gear and bed down at trailside campgrounds or basic hostels, to guided rides with catered meals and a soft bed in a country inn.

In Rockwood, Pa., a metal sculpture of a steam locomotive incorporates used bike and train parts.

The Great Allegheny Passage, or GAP, is among the most popular of the nation's rail trails, partly because of its proximity to major metropolitan areas, but also because of its abundance of life-affirming views amid forgiving terrain.

The trail, whether tackled whole or in smaller pieces, presents a recession-resistant getaway for a variety of budgets at a time of year when the Allegheny Mountains are rich in fall color.

Sister's Cafe in Confluence Pa. is a peddlers favorite because of the hearty breakfasts and delightful locals.

Thank goodness for the spare beverage holder on this bike.

The trail offers hours of uninterrupted smooth riding along rivers and the rail line.

The trail has recently been opened between Boston, Pa. and Homestead, Pa. The industrial town of McKeesport, Pa. is a bit of a shock to the system after the relative solace and beauty from Cumberland, Md. to Boston, Pa.

Mid October is the best time of year for leaf gazing along the GAP rail-trail.

Bikers stop to photograph their fellow riders at the Mason Dixon line between Maryland and Pennsylvania.

Beautiful vistas grace the trail near Frostburg, Md.

The trail follows the Youghiogheny River into Connellsville, Pa.

Stunning views along the Youghiogheny River.