Grandfather Falls
By Armen Suny · Last verified Sep 2026
LiDAR & 3D terrain
Photo Credits (3)
Difficulty
Easy
Trail Length
2.0 miles
Trail Type
Out And Back
About Grandfather Falls
Grandfather Falls, just upriver from Merrill on the Wisconsin River, is the river's highest waterfall — an 89-foot drop dispersed as a mile of cascades and rapids rather than a single vertical plunge. The series of falls unfolds across rocky ledges and offers a cinematic stretch of moving water and forested banks. Note that the upper third of the falls (and most of the flow except during spring snowmelt) is diverted through a canal and a set of penstocks to feed hydroelectric generators; the dam and power facility are owned and operated by Wisconsin Public Service Corporation, so seasonal flow can vary considerably. The site is a favorite for photographers, anglers, and hikers who appreciate dynamic river scenery more than a single dramatic drop. Several viewpoints along the river give good photo angles and listening spots for the rush of cascades. Visitors should exercise caution on slick rocks near the water and time visits for spring runoff if you want to see the falls at fuller volume.
The Setting
Grandfather Falls sits at 1,319 feet along the Prairie River, in the foothills of Wisconsin.
Trail & Hike Details
Trail Description
The access trail to Grandfather Falls is a 2.4-mile out-and-back route with about 350 feet of elevation gain, typically rated moderate in difficulty. The path follows the Wisconsin River and provides multiple lookout spots over the cascades; trail surfaces and conditions vary with season and weather. Expect a moderately steady climb on the return and take extra care near the river’s edge where rocks are often slippery. Because much of the upper flow is diverted to a hydroelectric canal except during spring runoff, plan your visit seasonally if you want higher water levels for photography or viewing.
What to Expect
Dogs are welcome.
Accessibility
The trail is not wheelchair accessible. Uneven terrain and elevation changes require steady footing.
Frequently Asked Questions
🐶 Are Dogs Allowed at Grandfather Falls?
✅ Dogs are allowed
Are There Any Fees or Permits Required?
🆖 No fees required
🏊 Is There Swimming at Grandfather Falls?
❌ Swimming is not allowed
When to Visit
Spring and fall are ideal times to visit due to cooler temperatures and vibrant foliage. Summer is also popular, but it may be busier.
Seasonal Access
The best time to visit is Spring, Summer, and Fall. Winter access may be limited.
Safety Information
Be cautious near the water, as rocks can be slippery and currents strong. Stay on marked trails to avoid getting lost. Check weather conditions before visiting, as the trail may become muddy or slippery after rain.
Current Water Conditions
81 ft³/s
Current discharge — how much water is flowing
Lower than usual for this time of year
Based on 105 years of record
2.01 ft
Water depth at gauge
7-Day Discharge Trend
What does this mean for your visit?
Flow is lower than usual for this time of year.
About This Gauge
This gauge is on a nearby waterway and may not reflect exact conditions at the falls.
7-Day Flow Outlook
Based on the USGS gauge PRAIRIE RIVER NEAR MERRILL, WI (13 km away).
Today
Moderate
81 cfs
9/10Tomorrow
Moderate
77 cfs
8/10Tue
Moderate
82 cfs
6/10Wed
Moderate
85 cfs
6/10Thu
Moderate
85 cfs
6/10Fri
Moderate
78 cfs
9/10Sat
Moderate
82 cfs
6/10Best window: Today — moderate flow, partly sunny (trip score 9/10).
Best time of year: this gauge typically runs highest from late March to mid June, peaking in April.
How we calculate this
This is a transparent outlook, not a precise forecast. We take the waterfall's current flow strength (how it ranks against its historical normal for today, from the nearest USGS stream gauge), carry that ranking forward along the gauge's seasonal curve, and nudge it for forecast rain. Confidence is highest for the next day or two and falls further out. Always check official conditions and your own judgment before visiting — high flows can be dangerous.
Know when to go.
Get a free email alert when waterfalls near Merrill hit peak flow. We only send when conditions are worth the trip — no weekly newsletters, no spam.
Weather Forecast
The Terrain, Seen by LiDAR
Aircraft-mounted lasers measured this ground to within inches. Trees and buildings are digitally stripped away, leaving the bare shape of the land the water has carved.
The bare-earth surface loses about 60 feet through the falls, but gradually, the profile of a cascade rather than a plunge. The ground at the falls is roughly 1,310 feet above sea level.
The ground changes about 106 feet in the 500 feet above the falls and 52 feet in the 500 feet below. The falls face southeast and sit in full sun for most of the day, best photographed early or late.
Drag to compare. The dot marks the waterfall. The frame is about a mile across.
- Ground elevation
- 1,310 feet
- Measured by 3-meter lidar
- Drop at the falls
- About 60 feet
- Change in ground height within ~250 feet of the falls
- Faces
- Southeast
- Sunlit most of the day. Go early or late for softer light.
A slice through the lidar ground surface, from above the falls to downstream (heading southeast).
Elevation data: USGS 3D Elevation Program. Aerial imagery: USGS The National Map. Public domain.
Location & Access
Getting There
Grandfather Falls is located near Merrill, Wisconsin. Visitors can access the falls via a trailhead off Grandfather Dam Road. The area is managed by Wisconsin Public Service Corporation, as it is near a hydroelectric dam.
Get Directions on Google MapsParking
Parking is available near the trailhead on Grandfather Dam Road. Spaces may be limited, especially during peak seasons.
Elevation
1,319 feet above sea level
Coordinates
45.303856° N, -89.790410° W
Visitor Tips & Gear
Wear sturdy shoes as the trail may have uneven terrain. Bring insect repellent during the summer months. Be cautious near the water, as rocks can be slippery. Check weather conditions before visiting, as the trail may be muddy after rain.
Where to Stay
Woodland Inn & Suites
Cobblestone Inn & Suites - Merrill
Bridge Inn Tomhawk - 2nd Floor, 1 King Size Bed, Balcony, River View
Rodeway Inn & Suites Tomahawk
Browse vacation cabins and private rentals nearby
Unique outdoor stays — tents, yurts, and treehouses
Rent a campervan or RV for your waterfall road trip
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Additional Information
Nearby Attractions
Nearby attractions include Council Grounds State Park and the city of Merrill, which offers dining and shopping options.
Wildlife
The area is home to various bird species, deer, and other wildlife. Visitors may also see fish in the river.
Cities near Grandfather Falls
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