The Eau Gallie Causeway connects Eau Gallie, Florida (which merged with Melbourne in 1969), with SR A1A near Indian Harbour Beach, across the Indian River Lagoon. Located entirely within the Melbourne city limits, the causeway consists of a main bridge crossing over the Intracoastal Waterway and a relief bridge. The bridge is a key link in SR 518, Eau Gallie Boulevard, of which the causeway is a part.