Twin Bridges is a beloved bridge-jumping and swimming spot on the river near St. Anthony, Idaho — a summer institution for families, teens, and college students across the upper Snake River Valley. The name comes from the setup: an old abandoned bridge stands right beside the one still in use, and the deep, slow water beneath the old span makes for about the best bridge jumping around, with no traffic to dodge and easy parking nearby.

The jumping is the main event, and it's well suited to a range of nerve. There are two distinct levels to leap from — a lower point around 11 feet and a higher one around 17 feet — so you can start small and work your way up, and the water below is plenty deep for cannonballs, flips, and gainers. Locals consider it about as good and as “reasonably safe” as bridge jumping gets, with one firm caveat: keep clear of the rocks along the sides, which can be exposed depending on the water level.

There's more to it than jumping. A little rope swing often hangs under the bridge — a favorite of the little kids — and a path up the river makes a good put-in for a short, mellow float back down. For families with young children, there's a sandbar on the north side just upstream of the action, perfect for wading and splashing away from the jumpers. The slow current is ideal for simply hanging out in the water while you watch your friends show off.

A fun local curiosity: downstream of the little rock dam on the north side lie the sunken remains of an old car, washed here after an accident years ago. When the water is low and clear you can spot its chrome bumper from the rocks and swim down for a look — a quirky bit of underwater sightseeing that regulars love.

Part of the appeal is how welcoming and community-minded the spot is. Generations of upper-valley families and Rexburg-area college students have made Twin Bridges their go-to summer swimming hole, and there's a friendly, everybody-shares-the-water vibe on a busy afternoon. It's the kind of simple, free, small-town summer pleasure that keeps people coming back week after week.

A few practical notes: it's a popular place, so expect a crowd on hot, sunny days and holidays — though it handles a lot of people well, and you rarely wait long to jump. Bring water shoes for the rocky spots, sun protection, and drinking water, always check the water depth and clear your landing before jumping (levels change through the season), keep an eye on kids near the current, and pack out all your trash. For a classic, easygoing eastern-Idaho swimming hole, Twin Bridges is hard to beat.

Right off Highway 20, there's a great spot to swim, swing, and dive. There's pullouts for parking right next to the bridge. There's a rope swing under the railroad bridge and a little swimming hole to the North. As always be careful of water levels. There are rocks down the middle of the river on the North side. If they're covered, the water is high.

Less than 1/2 a mile down the road from the Monkey Rock waterfall, Hog Hollow Bridge is a favorite spot for adrenaline junkies to cool off. The place to jump is off the East side of the bridge where it's deeper. It's about a 25 foot jump, depending on the water level. Always be careful of fast moving water, as well as rocks and debris below the surface.

CAUTION: This jump is from an active roadway so please be careful and considerate of drivers. They do have the right of way on the bridge and the road is often traveled by large trucks who will have difficulty stopping for a swimmer that decides to run out in front of them while they're crossing a bridge.

PLEASE NOTE: Ton the roads leading to the Hog Hollow Bridge, the speed limit is 35 mph for the last mile. There are kids, cows, horses, and dogs along that road and many people tend to speed going to and from Monkey Rock. Slow down and stay safe.