Bass Island Brownstone Company Quarry

The Bass Island Brownstone Company Quarry is a historic stone quarry located on Basswood Island in Wisconsin. The excavated chambers are now filled with water.

This quarry operated from 1868 to 1893 and supplied high-quality stone for major building projects throughout the region. The material was used in the second Milwaukee County Courthouse and other significant structures.

Brownstone from this quarry shaped the regional building style and was incorporated into major structures like the Chicago Tribune building and Milwaukee's St. Paul's Episcopal Church. The local construction tradition reflects this deep connection to the extracted stone.

The quarry site is located within the Apostle Islands National Lakeshore and is only accessible by boat. Plan boat transportation to reach Basswood Island in advance.

The quarry walls display different shades of brown and red stone with occasional white streaks running through the thick layers. These natural color variations create a striking appearance as you explore the excavated site.

GPS coordinates: 46.83216,-90.75574

Latest update: December 14, 2025 18:06