My hiking group does these trips identified as overnighters. Don't get the term confused with a weekend trip, say, departing on a nice Saturday afternoon, staying in a hostel/motel/hotel, a brisk hike the next day and then going home in the early evening. No, they are definitely not that. Instead, they entail meeting at a rented bus at 11:30pm on a Friday night (after a full days work), traveling 3-4 hours in the night/"sleeping," and starting a climb up a mountain at 3-4 am in the dark. The hikes will last 12-16 hours and we'll head back for home late in the night.