Originally known as Arthurs Seat Road it was built in the 1850s to provide a road from the farms south of Melbourne and link the city with its southern bay settlements and sea defences at Point Nepean. By the turn of the 20th century it had come to be known as Point Nepean Road and in 1948 was officially named Nepean Highway. Between the 1950s and about 1980, the road was progressively upgraded to a divided highway between the City and Mordialloc. From Mordialloc to Frankston, the highway is an undivided four lane road. The widening of the Mordialloc Bridge, the last section of less than four lanes, was completed in early 2009. The Nepean Highway has kept the Metro Route 3 signage throughout the suburbs but is designated B110 at the town of Mornington.
At Glen Huntly Road, the speed limit increases to 80 km/h and the road widens to become an eight-lane divided highway. It is reduced to six lanes at Moorabbin, passing through Cheltenham and Mentone, and then to the 60 km/h or 70 km/h four-lane single carriageway after the roundabouts at Mordialloc. The highway then travels virtually along the foreshore of Port Phillip Bay, to Frankston, with several stretches of dual carriageway, and then up Olivers Hill, from which there are good views across Frankston and the bay.
In the late 1960s a bypass road was constructed in the suburb of Mount Eliza. Previously the highway travelled through the main shopping village. This section is now known as Mount Eliza Way. After passing through Mount Martha, the highway joins with the Mornington Peninsula Freeway, before turning toward the town of Dromana. Here the highway changes name again, to become Point Nepean Road – which was the former name of the entire highway in the early years of settlement. From here, Arthurs Seat is accessible, which gives views across the bay, and on a clear day, the skyscrapers of Melbourne are visible. Anthonys Nose is a point, or escarpment located on the southern shore of Port Phillip Bay, between Dromana and McCrae. The highway passes between "The Nose" and the shores of the bay. It was named by Charles La Trobe in 1839. In the 1920s "The Nose" was modified in order to combat the daily tides that blocked the highway. B110 leaves the highway at Sorrento to cross the bay to Queenscliff, via the ferry where it continues to Geelong, via Bellarine Highway, but the highway continues as a two lane road down to the seaside resort of Portsea. The end of the highway is the very nondescript painted turning circle, before the gates of the former Commonwealth quarantine and defence station of Point Nepean, a humble ending to Melbourne's main southern highway.
