Highway18A was a short route that served the headland that protrudes into Lake Erie between Amherstburg and Kingsville in the southernmost part of Essex County. It began and ended at junctions with the former Highway18, now Essex County Road 20, that are approximately  apart on that road.
Highway18A was a brief route serving the headland projecting into Lake Erie between Amherstburg and Kingsville in southern Essex County. It commenced and concluded at locations where it intersected with former Highway18, now designated as Essex County Road 20, which are roughly the same distance apart.