A river rising in northern West Virginia and flowing about 206 km (128 mi) generally north into southwest Pennsylvania, where it joins the Allegheny River at Pittsburgh to form the Ohio River.

Colloquially known as "the Mon" or "Mon" or "that dirty thing you should never swim in." It actually makes for a fantastic boat ride in the summer, and I enjoy taking a dip in the river when it is sufficiently hot outside. It is, however, not a very clean river. Large amounts of mine drainage flow into the river all year long. (In fact, 3 years ago, the mine in Fredericktown, PA was leaking so much drainage that it began flowing into the street, weaving its orange path to the river. People complained, and after almost a year, yes, a YEAR, a pipe was installed to facilitate the flow. Didn't stop the problem, but now it's not as noticible. *sigh*)

Don't eat the fish, please.