The Highgate 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.
Highgate’s center stands about 260 ft above sea level. Within three miles the land runs from 90 ft to 440 ft, a difference of 350 ft: rolling country. The highest named summit within 15 miles is Leach Hill, about 1,430 ft, 13 miles southeast.
The section below crosses 6 rock units mapped at the surface.
Heights every 0.1 mile from the Copernicus GLO-90 surface model; vertical exaggeration about 18×. The colored band under the surface is the rock the state geologic map shows at the surface, not a picture of what lies beneath.
Slate. Age: Cambrian to Early Ordovician, 471 to 542 million years old. About 9 mi of the line.
Slate. Age: Ordovician, 445 to 487 million years old. About 2 mi of the line.
Slate, sedimentary-breccia, dolostone. Age: Cambrian, 487 to 542 million years old. About 1 mi of the line.
Quartzite. Age: Early Cambrian, 521 to 542 million years old. About 1 mi of the line.
Dolostone. Age: Early Cambrian, 521 to 542 million years old. About 1 mi of the line.
Dolostone. Age: Cambrian to Early Ordovician, 471 to 542 million years old. About 0.5 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 Highgate reaches the St. Lawrence River by way of Saxe Brook and the Richelieu: about 130 river miles. The St. Lawrence carries it on to the Atlantic.
Lake on the way: Lake Champlain.
80 miles of the trip are on the Richelieu.
Traced down the USGS NHDPlus V2.1 river network from the Census center point of Highgate; river miles along the main stem, rounded.