Anaconda Smelter Stack

The Anaconda Smelter Stack is the tallest surviving masonry structure in the world, with an overall height of about 585 feet, including a brick chimney 555 feet tall and the downhill side of a concrete foundation 30 feet tall. It is a brick smoke stack or chimney, built in 1918 as part of the Washoe Smelter of the Anaconda Copper Mining Company at Anaconda, Montana, in the United States. A terra cotta coating covered the entire brick chimney when new, but by the time the smelter closed in 1981, most had eroded away except for the upper 40%, exposing most of its bricks and reinforcing rods. The inside diameter at the bottom of the brick chimney is 76 feet while that at the top is about 60 feet. The stack and its viewing area are now the two-part Anaconda Smoke Stack State Park.

Source: Wikipedia