SR 200 passes along the Southern edge of Riverdale.

Incorporation of this city is fairly recent, occurring when the US Army Corps of Engineers turned the townsite over in the late 1980's. It lies along Government bay. The city was originally the site of housing for government workers and contractors during the construction of Garrison Dam from 1946 to 1950. Although the population here is small, the Summer brings many visitors for weekend stays. The Garrison Dam National Fish Hatchery and Aquarium is an interesting place to visit. It has several 300-gallon aquariums holding many of the fish species found in North Dakota waters. The the Downstream campground can be accessed by trails from the hatchery.