Past the impressive-but-crowded overlooks of Great Falls Park’s namesake on the Virginia side, and about a mile-and-a-half in on the River Trail, Cow Hoof Rock juts out more than 200 feet above the Potomac. This spot isn’t for anyone scared of heights or for the kids you want to keep. On warm weekends, it can get crowded with other hikers who want a peek. But if you can snag a little alone time on Cow Hoof, the view of the river and the dramatic cut of Mather Gorge is fantastic. The rock is split, hence the name, and sits across from the tennis-shoe scramblers on Maryland’s Billy Goat Trail, which makes for good people-watching should you get bored with the scenery. The best time to get there is late afternoon on a warmish winter day (great light, fewer people). Past the rock, the trail continues uphill some and then turns into the Ridge Trail, taking you down to river level (popular with mountain bikers) or west to the hiker-only Swamp Trail for a decent loop back to the visitor’s center and parking. It’s $5 to get in, unless you have a park pass.