The Interior plate. Relief from Copernicus GLO-30; rivers and lakes from USGS NHD; watersheds from the USGS Watershed Boundary Dataset; roads and city limits from Census TIGER 2024.
Interior’s center stands about 1,350 ft above sea level. Within three miles the land runs from 1,160 ft to 1,670 ft, a difference of 510 ft: hilly country. The highest named summit within 15 miles is Big Rock, about 1,530 ft, 8 miles southwest.
Under the town center the state geologic map shows Jacobsville Sandstone, from the Mesoproterozoic, 1 to 1.6 billion years old.
The section below crosses 3 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 25×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Sandstone. Age: Mesoproterozoic, 1 to 1.6 billion years old. About 14 mi of the line.
Mixed-clastic, metagraywacke. Age: Paleoproterozoic, 1.6 to 2.5 billion years old. About 9 mi of the line.
Basalt. Age: Paleoproterozoic, 1.6 to 2.5 billion years old. About 1 mi of the line.
From the USGS State Geologic Map Compilation (Horton and others, 2017), the states’ geologic maps joined at a common scale.
Heights from Copernicus GLO-90 (a surface model: it includes buildings and tree canopy); summits from USGS GNIS; rivers from USGS NHDPlus HR; rock from the USGS State Geologic Map Compilation.
A raindrop that lands in Interior reaches Lake Superior by way of Payseor Creek, Trout Creek, the Middle Branch Ontonagon and the Ontonagon: about 50 river miles. From there it moves on through the Great Lakes, over Niagara Falls and down the St. Lawrence to the Atlantic.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Interior; river miles along the main stem, rounded.