For all the joy to be found beside lakes and rivers, in valleys and on summits, ridgelines have one big advantage over other terrain: You can follow them for miles, with the world falling away to either side of the narrow trail. Sure, it usually means tough hiking, but once you’re up there, you can spend an entire day enjoying the kind of panoramic views that you’d only find once or twice on lesser hikes. These ten trails will give you all of that and more, from a park world-famous for its biodiversity to a weeklong traverse along the spine of an island.