[2] In 2011 the boundaries of the district were expanded to include four additional buildings on the west side of the 900 block of Main Street.

The buildings located on the east side of Main Street have exposed foundations along the alley because the grade descends in that direction.

The bell tower of St. Luke's United Methodist Church (1896) is equivalent to an eight-story building.

[2] St. Luke's Church and the Interstate Power Company Building (1894, 1956) are individually listed on the National Register.

This article about a property in Dubuque County, Iowa on the National Register of Historic Places is a stub.