Torch River is a short river in the U.S. state of Michigan. The river is part of the Chain of Lakes in Northern Michigan, flowing out of the south end of Torch Lake near the community of Torch River and emptying into Lake Skegemog. The river forms part of the boundary between Kalkaska County on the east and Antrim County on the west.

Torch Lake at 19 miles (31 km) long is Michigan's longest inland lake and at approximately 18,770 acres (76 km²) is Michigan's second largest inland lake. Portions lay within several townships in Antrim County, including Torch Lake Township, Central Lake Township, Forest Home Township, Helena Township, and Milton Township. Several villages and hamlets lie along its shore, including Alden, Eastport, Clam River, and Torch Lake. The lake is about 17 miles (27 km) northeast of Traverse City and is separated by narrow strips of land from both Grand Traverse Bay on the northwest and Elk Lake at the southwest end . The lake is about two miles (3.2 km) wide and is centered at 45°59'N 85°18'W / 45.983°N 85.3°W / 45.983; -85.3. It has a maximum depth of 330 feet (100 m) and an average depth of 111 feet (34 m), making it Michigan's deepest inland lake. It is a popular lake for fishing, featuring lake trout, rock bass, yellow perch, smallmouth bass, muskellunge, ciscoes, brown trout, rainbow trout, and whitefish.

The name of the lake is not due to its shape, rather, is derived from translation from the Ojibwa name Was-wa-gon-ong meaning "Place of the Torches", referring to the practice of the local native American population who once used torches at night to attract fish for harvesting with spears and nets. For a time it was referred to by local European settlers as "Torch Light Lake", which eventually was shortened to its current name.

The Grass River is a short (about two and a half mile-long) river in Antrim County in the U.S. state of Michigan. It is part of a watershed that begins in northern Antrim County with Intermediate Lake, which is connected by the Intermediate River with Lake Bellaire. The Grass River flows from Lake Bellaire into Clam Lake, which in turn drains into Torch Lake via the short Clam River. Torch Lake itself is drained by the Torch River, which flows into Lake Skegemog, which opens into Elk Lake. Elk Lake flows into the east arm of Grand Traverse Bay at Elk Rapids.

The Grass River Natural Area is a park of over 1,160 acres (4.7 km²) of wetlands and wildlife habitat purchased since 1969 by the non-profit group Grass River Natural Area, Inc. There are 3.5 miles (6 km) of boardwalk trails, bridges, and observation platforms that provide easy access to river, stream, lake and wetlands.