Montello is a city in and the county seat of Marquette County, Wisconsin, United States. The population was 1,495 at the 2010 census. The Fox River flows through the city. Montello is home to the largest tree in Wisconsin. A notable attraction in the city is the former granite quarry, which has been transformed into a park with several waterfalls.
According to the United States Census Bureau, the city has a total area of 2.15 square miles (5.57 km2), of which, 1.91 square miles (4.95 km2) is land and 0.24 square miles (0.62 km2) is water.
The Fox River flows from east through the middle of Montello. There is a dam in Montello, and the upstream portion of the river to the west of the dam is called Buffalo Lake.
The Montello River flows from the North meeting the Fox at the south end of Montello. The upstream portion of the river above the other dam is Montello Lake.
As of the census of 2010, there were 1,495 people, 628 households, and 356 families residing in the city.