Dundas is an unincorporated community in Vinton County, in the U.S. state of Ohio. It is located near the junction of State Route 324 and State Route 93.
Dundas was established in 1857 as McArthur Junction when the B&O railroad was extended to that point.[1] A post office called Dundas was established in 1856 and remained in operation until 1983.[2]