M-34 is an east–west state trunkline highway in the southeastern region of the US state of Michigan. It has a western terminus near Osseo on M-99 and runs through forest and farm lands to its eastern terminus at Business US Highway 223 (BUS US 223) and M-52 in Adrian. The highway serves a number of smaller communities in the area and intersects two US Highways while carrying between 4,200 and 11,300 vehicles on a daily basis. M-34 was designated and signed with the beginning of the state highway system around July 1, 1919, along a route that extended to either end of its current routing. These western and eastern extensions were added to other highways during the 1920s, shortening M-34 to roughly its current length. A few more changes were made in the mid-1950s and 1960s resulting in the modern routing. M-34 has a short, unsigned sibling, Connector 34, which is better known as Industrial Drive in the Adrian area. Route description M-34 begins at an intersection with M-99 just west of Osseo. M-99 approaches Osseo from the west along Hudson Road and where M-99 turns south along Pioneer Road, M-34 continues east along Hudson Road. The highway turns to the southeast to the south of Osseo near Deer Lake and continues towards Pittsford. Hudson Road runs through a mix of forests and local farms. The trunkline passes to the south of the main business district in Pittsford. East of town, the highway turns east and intersects US Highway 127 (US 127) at the Hillsdale–Lenawee county line in Hudson. The trunkline continues eastward through the city of Hudson as Main Street. On the eastern edge of town, it becomes Carleton Road and passes through more farmland. Just south of Clayton, M-34 has a junction with the northern terminus of M-156, a connector highway that runs south into Ohio and US 20. Approximately four miles (6.4 km) east of that junction, M-34 turns north for about two miles (3.2 km) along Benner Highway and passes through the community of Cadmus. At the end of its course along Benner Highway, M-34 turns east towards Adrian on Beecher Road. There are some residential subdivisions along the road on the southwest side of Adrian. M-34 intersects Industrial Drive and crosses US 223 and Beecher Road becomes Beecher Street in town. The trunkline continues east and terminates at the intersection of Beecher and Main streets