The wreck of the SS Cheviot was the worst loss of life at Port Phillip Heads. She was a schooner-rigged iron screw steamer of 1,226 tons and 70 m, built by Charles Mitchell & Co at Newcastle upon Tyne in 1870, on the Melbourne–Sydney coastal run. On the night of Wednesday 19 October 1887, shortly after clearing the Heads in a rising south-westerly, her propeller shaft broke; unable to steer or make way, she was driven back onto the ocean side of Point Nepean and struck at 9 pm in the bay that now carries her name. She broke in two in the surf. Of the 69 people aboard, 35 survived and 34 died, many within sight of the shore, and the disaster led directly to the establishment of the Queenscliff lifeboat station's rocket apparatus and to reforms in the pilot service.

The Scuba Doctor listing describes the wreckage as 'widely scattered', both because of 'the terrible beating it gets from the weather' and because of 1960s blasting for scrap; much of it lies in very shallow water and is visible at low tide, with the rest across the reef and sand to about 7 m. What remains – plating, frames, machinery fragments – is kelp-covered and sheltering crayfish and abalone, with the sweep, wrasse and zebrafish of the back-beach reefs over it. Cheviot Beach behind the site is closed to the public: it is the beach from which Prime Minister Harold Holt disappeared while swimming in December 1967.

The listing is clear that the site is 'highly prone to surge and turbulence' and can be dived 'only on exceptionally calm days'. It is dived rarely, by club boats, on the ebb, and it is a site for wreck historians rather than a scenic dive; a protected historic shipwreck under the Heritage Act.

Boat access only. Charter boats leave from Portsea Pier (Dive Victoria Group, Bayplay) and Queenscliff Harbour (Dive Victoria Group, Red Boats); run time is about 18 minutes. Private boats launch at Sorrento Boat Ramp (Point Nepean Road, Sorrento, all-tide concrete ramp with trailer parking) or Queenscliff Boat Harbour ramp (Larkin Parade, Queenscliff), roughly 20 minutes to the site.

The site is in Cheviot Bay on the ocean side of Point Nepean, reached out through the Heads and east along the back beaches (about 20 minutes from Portsea or Sorrento); Cheviot Beach is closed national park land – the beach from which Prime Minister Harold Holt disappeared in 1967 – and there is no shore access. Skippers must call Lonsdale VTS (Point Lonsdale) or listen to VHF 12 for shipping movements before dropping divers, and must carry a dive flag; anchoring is not permitted in the shipping channel, so a live boat and a drop-shot or drift float is the normal method.

It is dived on the ebb slack or a gentle ebb only, when the outgoing tide leaves this side of the reef in relatively still water. Slack water at Port Phillip Heads does not coincide with high or low water: it falls roughly three hours after high or low water at Point Lonsdale, and the usable window is typically 20–40 minutes. Use the Ports Victoria / Port of Melbourne slack-water predictions for The Heads (also republished by charter operators and WillyWeather 'Rip Bank') rather than a standard tide table.

Being outside or right at the entrance, it is exposed to Bass Strait swell: anything over about 1.5 m from the south-west or south, or a strong southerly/westerly wind against the ebb, produces standing waves in The Rip and charters cancel. Northerlies flatten the entrance and give the best days. Visibility is best in late summer and autumn (Feb–May) when the water is clear and the westerlies have eased; winter brings 11–13 °C water and bigger swells but often the clearest days after a run of settled weather.

Heavy rain has little effect this close to the ocean. The listing: 'highly prone to surge and turbulence' and diveable 'only on exceptionally calm days due to proximity to The Rip and potential cross currents'. Tide reference WillyWeather 'Cheviot Beach'.

Live drop on the ebb on an exceptionally calm day, descend onto the scattered iron at 3–7 m and work through the debris field with the swell behind you; keep it short, stay clear of the surf zone where the shallowest wreckage lies, and ascend under a DSMB for pick-up outside the bay.

No regular scheduled charter – dived from private and club boats (VSAG, Power House Underwater Club, Scuba Diving Melbourne) and occasionally by Dive Victoria Group or Red Boats when a group requests it.