US 45 crosses from Wisconsin to Michigan near Land O' Lakes, Wisconsin, east of the Sylvania Wilderness area of the Ottawa National Forest. The highway angles northeast from the state line before curving around to the north toward Watersmeet, where it intersects US 2. Watersmeet is home to the northern section of the Lac Vieux Desert Indian Reservation. Continuing north across the Gogebic–Ontonagon county line, US 45 crosses the boundary between the Central and Eastern time zones. In southern Ontonagon County, the highway runs west of the Bond Falls Flowage near Paulding. North of here, the trunkline enters Bruce Crossing and intersects M-28. After leaving town, US 45 runs northward parallel to the Middle Branch of the Ontonagon River, and the highway crosses the river near a roadside park south of Rockland. East of Rockland, US 45 meets the southern terminus of M-26; after the intersection, US 45 turns northwesterly and runs parallel to the Ontonagon River and a snowmobile trail. US 45 enters the south side of Ontonagon on Rockland Road near the Holy Family Cemetery. The roadway turns due north, still running parallel to the course of the river. South of downtown, the highway crosses an intersection that serves as the joint termini of M-38 and M-64. M-64 crosses the river from the west on a bridge built in 2006 and ends at the intersection. M-38 comes into town from the east and also ends at the same intersection. US 45 continues north on Rockland Road and turns northwest on River Street along the eastern river bank through downtown. The northern terminus of US 45 is at Ontonagon Street, about from Lake Superior.
History
US 45 debuted in Michigan by 1935 on maps of the time. The highway previously terminated in Des Plaines, Illinois, until it was extended northward to Michigan. US 45 replaced M-26 between the state line north toward Rockland, as well as M-35 between Rockland and Ontonagon. The Michigan State Highway Department rebuilt an section of the highway in the Military Hills area of eastern Ontonagon County starting in 1957. As part of the project, tons of waste copper rock were hauled into the area to provide a base for the reconstructed roadway, which was previously quite steep through the hills and muddy during rains. The project included a new bridge over the Ontonagon River that opened in late 1959. Along with this bridge, the last of US 45 in the country were paved, connecting the Gulf of Mexico and Lake Superior with a hard-surfaced road. A rerouting in late 1971 moved the US 45 designation along M-26 between Rockland and Greenland. From Greenland, US 45 followed Ontonagon–Greenland Road to Ontonagon. In late 1973, MDOT reversed the rerouting—US 45 was restored to its previous routing on Rockland Road between Rockland and Ontonagon and M-26 was re-extended south from Greenland to Rockland; M-38 was extended west along Ontonagon–Greenland Road. In 2010, students from Michigan Technological University solved the mystery of the Paulding Light, a local phenomenon commonly attributed to paranormal activity. The phenomenon is viewable from a section of Robbins Pond Road, the former routing of US 45 in the Paulding area. According to area folklore, and indicated on signs in the viewing area, the light is from the ghost of a railroad brakeman. Other explanations say the light comes from a ghost train from the 19th century. The students' investigation showed that the light comes from headlights of cars on US 45 in the Paulding area.
