Union Falls

Drop everything

Is it plungeworthy?

260feet tall

A segmented on Mountain Ash Creek.

Scale59/60

Documentation20/20

Character14/20

The details

Type: Segmented
Watercourse: Mountain Ash Creek
Coordinates: 44.19226, -110.8708

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About Union Falls

Union Falls is a 260-foot segmented in Wyoming, on Mountain Ash Creek.

Fed largely by snowmelt, it runs hardest in late spring and early summer and can thin to a trickle by late season.

Plungeworthy rates Union Falls 9.3/10 — drop everything. The score weighs its scale, how confidently it's mapped, and its character.

What you'll find

The Bechler country's 250-foot crown: two streams merging mid-air into a single lace veil, deep in Yellowstone's least-visited corner. Sixteen round-trip miles keep the guest list short.

Getting there

Trailhead: Grassy Lake Trailhead (or Cave Falls with river fords)
Parking: Small unpaved lot
Road: Grassy Lake Road — hard-gated until June 1 every year for grizzly migration, often mud-bound weeks longer
Hike: 16 mi round trip, 700 ft of climb (hard)
Heads up: A huge day or an overnight with a backcountry permit. No cell, real bears, river levels that matter.

When to go

Late June through September — the annual road gate sets the season, not the snow you can see.

Rules & fees

Fee / pass: Yellowstone entrance fee; backcountry permit to camp
Dogs: Not on trails
Camping: Backcountry sites by permit; Flagg Ranch frontcountry near the road
Warnings: Check bear activity and fords before committing; this is the deep end.

Researched from NPS — backcountry trip planner · Wikipedia — Yellowstone waterfalls. Conditions change — verify before you drive. Been to Union Falls recently? Post a conditions report below.

Where it is

Before you go

The pin marks the feature, not a trailhead or a legal route in. Some sit on private land or need a real hike, and conditions change with season and rain. Check local access, don't trespass, and never enter water — hot or cold — where it isn't safe.