Big Bay Town Park: Lake Superior Agate & Jasper Rockhounding in Ashland County, Wisconsin

Public accessBest spot4 mineralsAshland County, WisconsinUpdated July 2026

Minerals reported: 4
Elevation: 590 ft
Best months: April to October

Big Bay Town Park on Madeline Island gives collectors a Lake Superior beach reachable by the Bayfield ferry. The long pebble and sand beach along Big Bay yields Lake Superior agates, jasper, and basalt cobbles, some carrying zeolite and thomsonite amygdules. The town park is public and open to collecting, in contrast to the adjacent Big Bay State Park, where rock removal requires written state permission. Reported finds include lake superior agate, jasper, thomsonite, basalt. Below: coordinates, access notes, nearby spots, and trip-planning links.

Plan your visit

Generally open to casual rockhounding

County: Ashland County
State: Wisconsin
Nearest road: Hagen Road
Postcode: 54850
Coordinates: 46.78460, -90.64780

Get directions View on Google Maps

Coordinates are approximate. Confirm the exact ground in the RockHoundR app, where land overlays show which agency manages the area.

Land & collecting status

Generally open to casual rockhounding

Most public-tagged spots sit on BLM, U.S. Forest Service, or other federal land where reasonable hand collecting of common rocks and minerals is allowed. Confirm posted rules and active mining claims before you dig.

Access note: Big Bay Town Park is a free Town of La Pointe park on Madeline Island, reached via the Madeline Island Ferry from Bayfield. Collect by hand on the public town-park beach; the neighboring Big Bay State Park does not allow casual collecting. Best picking is along the gravel concentrations after wind events.

Public-land rules vary by agency, season, and field office. The RockHoundR app pulls live BLM, USFS, NPS, and tribal overlays so you can see exactly which agency manages the ground at this spot.

Best time to visit Big Bay Town Park

22°J

27°F

37°M

49°A

61°M

71°J

77°J

76°A

68°S

54°O

40°N

28°D

Comfortable months (45 to 90°F highs)

Best months: April to October. Typical highs run 77°F in midsummer and 22°F in midwinter, with winter lows near 7°F.

Climate normals: NOAA 1991-2020 monthlies, MADELINE IS station (6 mi away).

Geology at Big Bay Town Park

This spot sits on ground mapped as water. Tough silica like agate and jasper typically survives weathering and collects as float in drainages and gravel.

Mapped unit: water
Elevation: 590 ft

Geologic mapping via Macrostrat and the underlying state geological survey maps (CC BY 4.0). Bedrock at the surface can vary within a mapped unit.

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Sources & verification

Spot details combine the public RockHoundR location dataset, normalized mineral labels, agency land-status checks in the app, and community submissions. Coordinates are approximate until verified in the field.

Wisconsin Geological and Natural History Survey
Wisconsin DNR property rules
Chequamegon-Nicolet National Forest
Community submissions reviewed against published agency rules

Found at Big Bay Town Park

Each name opens all spots that produce that material; the encyclopedia link opens the full ID and field guide.

Nearby rockhounding spots

Other rockhounding spots within driving distance of Big Bay Town Park.

Saxon Harbor County ParkIron County, Wisconsin · 18 mi awayLake Superior Agate, Jasper, Copper
Near Saxon FallsIron County, Wisconsin · 21 mi awayCalcite, Chlorite, Epidote
General AreaAshland County, Wisconsin · 25 mi awayCopper
HerbsterBayfield County, Wisconsin · 29 mi awayGranite, Agate, Banded Iron Formation
Iron CountyIron County, Wisconsin · 29 mi awayAgate, Jasper
Montreal MineIron County, Wisconsin · 32 mi awayActinolite, Barite, Selenite
Iron CountyIron County, Wisconsin · 32 mi awayCopper
Port Wing MarinaBayfield County, Wisconsin · 35 mi awayGranite, Agate, Banded Iron Formation

Across the state line from Big Bay Town Park

Big Bay Town Park is close enough to the Wisconsin border that the next-closest rockhounding spots are in a neighboring state. Worth knowing if you are already on the road.

Little Girls Point County ParkGogebic County, Michigan · 20 mi awayBasalt, Granite, Unakite
Maple CreekGogebic County, Michigan · 27 mi awayGranite, Agate, Banded Iron Formation
Black River HarborGogebic County, Michigan · 30 mi away
Gull RockLake County, Minnesota · 45 mi awayLake Superior Agate
Beaver BayLake County, Minnesota · 45 mi awayLake Superior Agate, Thomsonite
Union Bay CampgroundOntonagon County, Michigan · 48 mi away

Big Bay Town Park FAQ

Where is Big Bay Town Park?+

Big Bay Town Park is in Ashland County, Wisconsin, at 46.78460, -90.64780. Nearest road: Hagen Road.

What rocks and minerals can you find at Big Bay Town Park?+

Big Bay Town Park is reported to produce Lake Superior Agate, Jasper, Thomsonite, Basalt.

Is collecting allowed at Big Bay Town Park?+

Generally open to casual rockhounding. Most public-tagged spots sit on BLM, U.S. Forest Service, or other federal land where reasonable hand collecting of common rocks and minerals is allowed. Confirm posted rules and active mining claims before you dig. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Big Bay Town Park?+

Most agate and jasper is surface float: bring a spray bottle, a pick or small shovel, and a sturdy bag. Wet stones show their banding and translucence.

When is the best time to visit Big Bay Town Park?+

The most comfortable months at Big Bay Town Park are April to October.

How do I get to Big Bay Town Park?+

Open the directions link to navigate to 46.78460, -90.64780 in Google Maps. The nearest road is Hagen Road.

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