The Charles River, sometimes called the River Charles or simply the Charles, is an 80-mile-long river in eastern Massachusetts. It flows northeast from Hopkinton to Boston along a highly meandering route, that doubles back on itself several times and travels through 23 cities and towns before reaching the Atlantic Ocean. The indigenous Massachu…The Charles River, sometimes called the River Charles or simply the Charles, is an 80-mile-long river in eastern Massachusetts. It flows northeast from Hopkinton to Boston along a highly meandering route, that doubles back on itself several times and travels through 23 cities and towns before reaching the Atlantic Ocean. The indigenous Massachusett named it Quinobequin, meaning "meandering" or "meandering still water".