WI · ranked by public data

The 23 Biggest Lakes in Florence County, Wisconsin

23 Florence County lakes cover at least 50 acres, out of 108 documented lakes in the county. Updated July 2026.

1506 ac
506 acres
Florence County, WI
Halsey Lake
enhancedDepth mapWater data
45.85, -88.63506 acres | 10 ft max1 public access pointLargemouth Bass, Northern Pike
506 acres · 10 ft max depth · 1 public landing
2353 ac
353 acres
Florence County, WI
Long Lake
enhancedDepth mapWater data
45.84, -88.68353 acres | 21 ft max1 public access pointNorthern Pike, Panfish
353 acres · 21 ft max depth · 1 public landing
3297 ac
297 acres
Florence County, WI
Brule River Flowage
enhancedDepth map
45.95, -88.22297 acres | 64 ft max0 public access pointsSmallmouth Bass, Walleye
297 acres · 64 ft max depth · No verified public access
4272 ac
272 acres
Florence County, WI
Fay Lake
enhancedDepth mapWater data
45.87, -88.64272 acres | 10 ft max1 public access pointLargemouth Bass, Northern Pike
272 acres · 10 ft max depth · 1 public landing
5254 ac
254 acres
Florence County, WI
Patten Lake
enhancedDepth mapWater data
45.85, -88.42254 acres | 52 ft max1 public access pointPanfish, Largemouth Bass
254 acres · 52 ft max depth · 1 public landing
6195 ac
195 acres
Florence County, WI
Keyes Lake
enhancedDepth mapAIS recordedWater data
45.90, -88.31195 acres | 74 ft max1 public access pointLargemouth Bass, Panfish
195 acres · 74 ft max depth · 1 public landing
7183 ac
183 acres
Florence County, WI
Emily Lake
enhancedDepth mapWater data
45.87, -88.28183 acres | 43 ft max1 public access pointLargemouth Bass, Walleye
183 acres · 43 ft max depth · 1 public landing
8130 ac
130 acres
Florence County, WI
Ellwood Lake
enhancedDepth mapWater data
45.86, -88.14130 acres | 25 ft max1 public access pointPanfish, Smallmouth Bass
130 acres · 25 ft max depth · 1 public landing
9123 ac
123 acres
Florence County, WI
Pine River Flowage
enhancedDepth mapWater data
45.83, -88.27123 acres | 35 ft max2 public access pointsWalleye, Northern Pike
123 acres · 35 ft max depth · 2 public landings
10114 ac
114 acres
Florence County, WI
Sea Lion Lake
enhancedDepth mapWater data
45.88, -88.32114 acres | 82 ft max1 public access pointPanfish, Largemouth Bass
114 acres · 82 ft max depth · 1 public landing

Rank	Lake	County	Acres	Max depth	Public access
11	Bass Lake	Florence	104 ac	68 ft	—
12	Reisner Lake	Florence	96 ac	5 ft	—
13	Lost Lake	Florence	84 ac	45 ft	1 landing
14	Middle Lake	Florence	83 ac	54 ft	—
15	North Lake	Florence	79 ac	43 ft	1 landing
16	Cosgrove Lake	Florence	76 ac	26 ft	—
17	Long Lake	Florence	73 ac	75 ft	—
18	West Lake	Florence	72 ac	25 ft	—
19	Lake of Dreams	Florence	62 ac	15 ft	1 landing
20	West Bass Lake	Florence	55 ac	19 ft	1 landing
21	Bass Lake	Florence	51 ac	42 ft	1 landing
22	Fisher Lake	Florence	50 ac	42 ft	2 landings
23	Seidel Lake	Florence	50 ac	44 ft	1 landing

Methodology

How this list is built

Ranked strictly by documented surface acres from DNR lake records.
Flowages and reservoirs count — they are lakes in the DNR's books, and some of the state's biggest water is impounded.
Lakes without documented acreage are excluded rather than estimated.
Lakes under 50 acres — or without documented acreage — are excluded from rankings.
Public access is shown for every lake but never affects the ranking.

FAQ

Florence County lake records

What is the biggest lake in Florence County?

Halsey Lake — Halsey Lake in Florence County is the biggest lake in Florence County, at 506 acres.

Biggest lakes statewide Deepest lakes in Florence County Clearest lakes in Florence County Lakes with the most public access in Florence County All Florence County lakes

Source data: Wisconsin DNR lake and monitoring records as aggregated by LakeList. Figures reflect the most recent documented values, not new surveys — verify access and rules before you go. Lake outlines are shoreline shapes from LakeList and the USGS National Hydrography Dataset; they illustrate a lake's form and are not depth or navigation charts.

WI · ranked by public data

The 23 Biggest Lakes in Florence County, Wisconsin

23 Florence County lakes cover at least 50 acres, out of 108 documented lakes in the county. Updated July 2026.

1506 ac
506 acres
Florence County, WI
Halsey Lake
enhancedDepth mapWater data
45.85, -88.63506 acres | 10 ft max1 public access pointLargemouth Bass, Northern Pike
506 acres · 10 ft max depth · 1 public landing
2353 ac
353 acres
Florence County, WI
Long Lake
enhancedDepth mapWater data
45.84, -88.68353 acres | 21 ft max1 public access pointNorthern Pike, Panfish
353 acres · 21 ft max depth · 1 public landing
3297 ac
297 acres
Florence County, WI
Brule River Flowage
enhancedDepth map
45.95, -88.22297 acres | 64 ft max0 public access pointsSmallmouth Bass, Walleye
297 acres · 64 ft max depth · No verified public access
4272 ac
272 acres
Florence County, WI
Fay Lake
enhancedDepth mapWater data
45.87, -88.64272 acres | 10 ft max1 public access pointLargemouth Bass, Northern Pike
272 acres · 10 ft max depth · 1 public landing
5254 ac
254 acres
Florence County, WI
Patten Lake
enhancedDepth mapWater data
45.85, -88.42254 acres | 52 ft max1 public access pointPanfish, Largemouth Bass
254 acres · 52 ft max depth · 1 public landing
6195 ac
195 acres
Florence County, WI
Keyes Lake
enhancedDepth mapAIS recordedWater data
45.90, -88.31195 acres | 74 ft max1 public access pointLargemouth Bass, Panfish
195 acres · 74 ft max depth · 1 public landing
7183 ac
183 acres
Florence County, WI
Emily Lake
enhancedDepth mapWater data
45.87, -88.28183 acres | 43 ft max1 public access pointLargemouth Bass, Walleye
183 acres · 43 ft max depth · 1 public landing
8130 ac
130 acres
Florence County, WI
Ellwood Lake
enhancedDepth mapWater data
45.86, -88.14130 acres | 25 ft max1 public access pointPanfish, Smallmouth Bass
130 acres · 25 ft max depth · 1 public landing
9123 ac
123 acres
Florence County, WI
Pine River Flowage
enhancedDepth mapWater data
45.83, -88.27123 acres | 35 ft max2 public access pointsWalleye, Northern Pike
123 acres · 35 ft max depth · 2 public landings
10114 ac
114 acres
Florence County, WI
Sea Lion Lake
enhancedDepth mapWater data
45.88, -88.32114 acres | 82 ft max1 public access pointPanfish, Largemouth Bass
114 acres · 82 ft max depth · 1 public landing

Rank	Lake	County	Acres	Max depth	Public access
11	Bass Lake	Florence	104 ac	68 ft	—
12	Reisner Lake	Florence	96 ac	5 ft	—
13	Lost Lake	Florence	84 ac	45 ft	1 landing
14	Middle Lake	Florence	83 ac	54 ft	—
15	North Lake	Florence	79 ac	43 ft	1 landing
16	Cosgrove Lake	Florence	76 ac	26 ft	—
17	Long Lake	Florence	73 ac	75 ft	—
18	West Lake	Florence	72 ac	25 ft	—
19	Lake of Dreams	Florence	62 ac	15 ft	1 landing
20	West Bass Lake	Florence	55 ac	19 ft	1 landing
21	Bass Lake	Florence	51 ac	42 ft	1 landing
22	Fisher Lake	Florence	50 ac	42 ft	2 landings
23	Seidel Lake	Florence	50 ac	44 ft	1 landing

Methodology

How this list is built

Ranked strictly by documented surface acres from DNR lake records.
Flowages and reservoirs count — they are lakes in the DNR's books, and some of the state's biggest water is impounded.
Lakes without documented acreage are excluded rather than estimated.
Lakes under 50 acres — or without documented acreage — are excluded from rankings.
Public access is shown for every lake but never affects the ranking.

FAQ

Florence County lake records

What is the biggest lake in Florence County?

Halsey Lake — Halsey Lake in Florence County is the biggest lake in Florence County, at 506 acres.

Biggest lakes statewide Deepest lakes in Florence County Clearest lakes in Florence County Lakes with the most public access in Florence County All Florence County lakes

The 23 Biggest Lakes in Florence County, Wisconsin

Halsey Lake

Long Lake

Brule River Flowage

Fay Lake

Patten Lake

Keyes Lake

Emily Lake

Ellwood Lake

Pine River Flowage

Sea Lion Lake

How this list is built

Florence County lake records

What is the biggest lake in Florence County?

The 23 Biggest Lakes in Florence County, Wisconsin

Halsey Lake

Long Lake

Brule River Flowage

Fay Lake

Patten Lake

Keyes Lake

Emily Lake

Ellwood Lake

Pine River Flowage

Sea Lion Lake

How this list is built

Florence County lake records

What is the biggest lake in Florence County?