The steep terrain around Lake Grapevine is popular with mountain bikers, but its rocky curves make it an equally challenging spot for hikers and joggers (just watch for the cyclists). The trail runs for 10 miles on the north side of the lake (30 miles northwest of Dallas), where you can also find lakefront camping, kayak rentals and other outdoor activities. In our otherwise pancake-flat North Texas landscape, this trail offers some of the best up-and-down hiking in a natural setting.