Pennsylvania may not be known for towering peaks, but several mountain ranges wind their way through the state. In fact, the midpoint of the Appalachian Trail is in Pennsylvania. Video above ...

Two experienced hikers were rescued from the tallest mountain in the Northeast ... had received training on hikes from the Appalachian Mountain Club's chapter in Worcester, Massachusetts.

The Himalayas, the highest mountains in the world, were created this way. (In fact, they're still growing.) So were the European Alps. Even the Appalachian Mountains formed when two land masses ...