Swimming in Yellowstone Lake is strongly discouraged, even forbidden at West Thumb. This is due to the extremely cold water after all, the lake’s elevation is nearly 8000 feet (3400 m). On a recent hot July day the surface water temperature behind Fishing Bridge Visitor Center was 55°F (13°C), but this was rare, and lakes like this one have colder layers beneath the surface. Signs at Bridge Bay are explicit: “Warning water extremely cold. Survival time limited to twenty minutes.” Boating is allowed from several launch sites, but motorboats are restricted to Grant Village and Bridge Bay Marina. Permits and flotation devices are required; see the “Travel Tips” for more information. Be careful when boating! The lake is famous for sudden squalls, especially in the afternoon, when waves can be as high as 6 feet. At least 40 drowning deaths have occurred on the lake in the park’s history; most have involved small boats. Fishing opens on June 15 th in Yellowstone Lake, but permits and regulations must be acquired first from a ranger station, visitor center, or general store.
See the “Living Things” and “Travel Tips” chapters for more about fish and fishing in the park. 19.6/1.0 g Elephant Back Trailhead. A 4-mile (6.4 km) trail with a loop at the top climbs Elephant Back Mountain about 800 feet (250 m) to a spectacular view of Yellowstone Lake. The mountain’s name, one of the park’s oldest, stems from the shape of its steep sides and rounded summit. Elephant Back Mountain is part of a very large 153,000-year-old lava flow. Early in the season, Elephant Back Trail may be closed due to grizzly bear activity in the area. Before you set out on a trail, it’s always best to inquire about safety at a ranger station or visitor center. Across the road from the trailhead, a short trail leads to Lake Lodge. 20.6/0.0 Fishing Bridge Junction (sometimes called Lake Junction). Fishing Bridge and the East Entrance are to the east; Mud Volcano, Hayden Valley, and Canyon Junction to the north; Lake Village, Bridge Bay Marina, and West Thumb to the southwest.