Black River is a 29.8-mile-long (48.0 km) river on the Upper Peninsula of the U.S. state of Michigan. The river flows into the Middle Branch Escanaba River in Ely Township of Marquette County at 46°23′53″N 87°46′15″W / 46.39806°N 87.77083°W and on into Lake Michigan. The river rises out of Goose Lake in northeast Republic Township at 46°28′19″N 87°59′46″W / 46.47194°N 87.99611°W and flows generally southeast through north-central Humboldt Township into Ely Township and the Middle Branch Escanaba River. Tributaries (from the mouth):