Browse Map

Explore away

Explore Map Collection

Check out our basemaps

Print a Map Plus

Generate a high-quality PDF

Field Guide

Discover local flora, fauna, geology, and more

Local Flora & Fauna

Learn the ecology of your area

Local Geology

Learn the geologic formation at your feet

Get Started or Sign In

Welcome

Continue with Apple

Already have an account? Sign In

MAP

Topo

Measure

Topo

Ecoregions

Public Lands

...

BASEMAPS

Default Weather

Temperature

Smoke

...

WEATHER

Saint Marys River

River in Swinney Park, Saint Mary’s River Wetlands Natural Area in Decatur in IN, OH

Indiana Fishing Regulations

Ohio Fishing Regulations

Print Map

Generate High-Quality PDF

Length

98mi

On the Web

On Wikipedia

The St. Marys River (Shawnee: Kokothikithiipi, in Miami-Illinois: Nameewa siipiiwi) is a 99-mile-long (159 km) tributary of the Maumee River (Miami-Illinois: Taawaawa siipiiwi) in northwestern Ohio and northeastern Indiana in the United States. Prior to development, it was part of the Great Black Swamp. Today, it drains a primarily rural farming region in the watershed of Lake Erie. It is formed in southern Auglaize County in western Ohio by the confluence of the short East Branch and Center Branch. It flows briefly west to St. Marys, approaching to within two miles of Grand Lake before turning to the north. In northwestern Auglaize County it turns sharply to the west-northwest, flowing past Rockford and Willshire into Adams County, Indiana. In northeastern Indiana it flows northwest past…

Classified As

River