Once you've completed several half marathons and regular marathons, what do you do when you want to test yourself even further? You tackle one of Tejas Trails' intense 50- or 100-mile races.

The races, of which there are eight others, unfold over the course of one or two days on trails of varying distances throughout Texas. Volunteers, race, and medical staff are available along with aid stations stocked with food and beverages. When the race ends and everyone hangs out in a serene setting, congratulating each other on a job well done, completing the challenge is worth it.