Pack a picnic lunch, lace up your most comfortable shoes, and hit these Pittsburgh trails that will take you to some pretty impressive ruins - from a century old factory to once vibrant coal towns that are now simply ghost towns. These six trails around Pittsburgh promise adventure at every turn.

1. Dead Man’s Hollow - McKeesport

Hike deep into the woods in McKeesport where you'll discover the ruins of a more than a century old factory. Embark on the Ruins Trail for .32 of a mile (orange on the trail map) and you'll arrive at the ruins. The area, however, boasts six miles of trails that pass a variety of sites, including the ruins and an enchanted staircase.

Dead Man's Hollow is located on Liberty Way in McKeesport. Click here to view the trail map.

2. Ghost Town Trail

Embark on an epic hike along the Ghost Town Trail, which spans 36 miles through Indiana and Cambria Counties. Whether you opt to hike all or part of the trail, you'll pass the remains of former coal towns, the Coal Miners Memorial, and the historic Eliza Furnace (pictured above).

Click here for more information and for a list of the trailheads.

3. Coal & Coke Trail

Hike past now dormant coke ovens along the Coal & Coke Trail that runs from Mount Pleasant to Scottdale. Enjoy breathtaking scenery as you travel along Jacob's Creek.

Click here for the trail map.

4. Linn Run State Park

Lace up your most comfortable hiking boots as you embark on the Flat Rock Trail, which runs only a half of a mile in Linn Run State Park. The highlight of the trail is, of course, the flat rock that's jutting out of a stream at the end of the hike. Be forewarned, however, that standing on the rock can be hazardous as it tends to be slippery.

Linn Run State Park is located at 770 Linn Run Road, Rector, PA 15677. Click here for more information.

5. Steel Valley Trail

Uncover Pittsburgh's rich steel industry history when you journey along the Steel Valley Trail. The trail spans a total of 19 miles and will take you past Carrie Furnace and the U.S. Steel Edgar Thomson Works. If you opt to hike the entire trail, you'll also travel through various neighborhoods, including West Mifflin, Duquesne, Homestead, Rankin, and Swissvale.

Click here for more information and a trail map.

6. West Penn Trail

Hike from Saltsburg to Blairsville, or vice versa, along the West Penn Trail. The 17 mile trail, which follows the river, ranges from easy to difficult in some spots and you'll pass the remnants of old buildings, canals, and stone arch bridges.

Click here for a trail map.

Pittsburgh's trails will take you to extraordinary ruins, amazing natural wonders, and even to some haunted places.