Hiking opportunities abound in Pennsylvania, thanks to the efforts of Keystone Trails Association, a public service organization that oversees the work of dozens of trail clubs and individuals who keep these footpaths cleaned up for those who want to enjoy wilderness.

This year, we're offering readers a glimpse of many scenic trails -- from easy jaunts to real workouts. Each month we'll feature a different trail in the hopes that you'll pull on a pair of boots and begin exploring on your own.

On the trail: Standing Stone Trail

Exciting things have been happening to Standing Stone Trail in the last decade -- not the least, its name.

Originally called Link Trail, it is a 70-mile-long link between the Tuscarora Trail (its southern terminus at Cowans Gap State Park) and Mid State Trail (at Greenwood Furnace State Park). The footway for the trail was laid out between 1978 and 1982, making use of old log slides and railroad grades and following the scenic ridge tops in Fulton, Huntingdon and Mifflin counties. Much of it lies within Rothrock State Forest or on state game lands.

Mel Cooper, Huntingdon, is a trail volunteer who helps keep this trail open. He appreciates its rugged contours through ridgetop outcroppings that appear along and in the trail.

"The Indians who lived in this area were referred to as 'the people of the standing stone'; I often wonder if these natural rock outcrops had something to do with that," Cooper said. He can't

pinpoint it, but he knows there's something different about the rocks, especially at Rocky Ridge Natural Area, where the Three Sisters formation stands.

"I can't state how they were formed, but they're a type of stone that the Climbing Conservancy (of Central Pennsylvania, out of State College) consider to be the best climbing stones in the east, and perhaps in the whole country," he said.

Parts of the trail have, until now, been along roads. To make way for its new role -- that of becoming part of the Great Eastern Trail from Alabama through New York, Standing Stone Trail, renamed in 2007, is being redesigned as much as possible. Southern sections are being rerouted this year. For that reason, Cooper said, the trail guide and maps may not be accurate. Before taking off, check the website.

"Our new design, as a premiere footpath, will be moving into the forest everywhere possible," said Cooper. "Tom Scully, the landscape architect (from the Harrisburg area), has done a lot of reroutes for the Appalachian Trail. Tom likes our philosophy."

Upside: Starting at the picturesque old church at Greenwood Furnace to the valley views of Amish farmlands, it's a unique experience. The immensity and nature of the rock outcrops is a plus, Cooper said -- not only on Rocky Ridge, but all along Jack's Mountain. Views from every mountaintop look down into green, sleepy valleys.

Downside: The most difficult and dangerous section -- Stone Mountain toward the northern end. "You'll do a lot of rock hopping," said Cooper. "It takes us about 10-11 hours to do 9 to 9.5 miles. We all carry walking sticks and ... watch our steps."

Heavy traffic makes road crossings difficult at Pa. 655 and U.S. 22, and there is about four to five miles of road walking from Meadow Gap (Pa. 475) to Three Springs.

Water may be an issue in sections, but two old farmsteads offer fresh spring water. Maps indicate water sources.

Highlights: Near Mapleton Depot are The Thousand Steps, a stone stairway rising from U.S. 22 up the mountainside to reach the quarries where silica was mined. Quarry workers built these steps then used them every workday. Silica was used to make a type of brick that could take heat -- "the brick that lined our steel blast furnaces, that built the steel for this country," Cooper said.

Take another peek at history near Vanderbilt's Folly, a section of abandoned stoneworks east of Fort Littleton left over from the Pittsburgh Vanderbilts' attempt to make an easier and cheaper railway through the mountains.

More breathtaking views are south of U.S. 22, said Cooper. In an area called the Throne Room (near Jack's Mountain Fire Tower), you can view two valleys at one time, where the foot of the mountain comes down to a point. Off Sinoquipe Road in Fulton County is Monument Rock, the model for the image on the SST patch.

Wildlife: In May, you look upon "scads of dogwood trees" near a new yellow-blazed trail called Dogwood Trail. In June, rhododendron fill some of the mountainsides. Turkey roost on the northwest side of Rocky Ridge. Cooper has seen coyote, bear, deer; 'we'll find bear deposits just about anywhere," he said, and he once saw three coyotes together, "doing a lot of calling."

Taking it easy: An easy day hike is to leave a car in the State Game Lands 112 parking lot and another at the Frew Road cul de sac in the Martins Gap Wild Area.

A short loop hike would use the SSTto Dogwood Trail.

Maps and trail guides: Both are available online at http://www.hike-sst.org. NOTE: Sections 7 and 8 updates are posted online.

For information about hiking trails in the state visit http://www.kta-hike.org.