Kitty Miller Bay is the shore dive most Phillip Island locals recommend first. It is a neat horseshoe of sand and cobbles on the island's south-west corner, adjacent to the Penguin Parade, enclosed by the basalt of Watt Point and Kennon Head and largely protected from the south-westerly swell that hammers the rest of this coast. Scuba Doctor calls it one of the island's best protected beaches and great for snorkelling and scuba diving, and Surf Life Saving records average waves of only 0.7 m.

The bay floor is seagrass and patchy weed at 2–4 m, with rock reef running out from both points to 8–12 m and a wide expanse of intertidal platform exposed at low tide when the beach opens out to 50 m wide. The diving is easy and varied: the seagrass holds rays, Port Jackson sharks and juvenile fish; the reef edges are kelp, coralline algae and sponge with zebrafish, leatherjackets, wrasse, morwong and old wives; and the gutters under the points collect crayfish and abalone. Spearfishing is common here and the site is also popular with families snorkelling the pools, so early mornings are quieter.

The western side is the gentler entry and the standard route; the eastern side under Kennon Head, with more swell and a rougher entry, gives access to better reef and, for experienced divers, a swim of 600 m round the point to the iron barque Speke, wrecked in 1906, whose remains lie in 0–26 m on the open coast (covered as a separate wreck site). The long walk from the car park is the main effort. Kitty Miller Bay suits new divers, snorkellers and anyone wanting a reliable Phillip Island shore dive in southerly weather, and it is the natural training venue on the island.

From Cowes follow Ventnor Road west towards the Penguin Parade for about 10 km, then turn left into Kitty Miller Road and follow it to the small car park behind the dune at its end (about 15 minutes from Cowes; 2 hours from Melbourne). Scuba Doctor warns it is a long walk from the car park down to the rocky beach – allow 5–10 minutes each way over sand and cobbles. Enter on the western side of the bay for the easiest reef, or on the eastern side under Kennon Head in calm weather.

The Speke wreck lies 600 m south-east around the point but is a separate, more exposed dive.

One of Phillip Island's best protected beaches, with waves averaging 0.7 m at the shore even when the open coast is bigger, because the bay is enclosed by Watt Point and Kennon Head and fronted by reef. Best after several days of still weather or northerly winds; a south-westerly swell above 1.5 m still pushes surge across the reef and reduces visibility. Enter on the receding tide – the lower the tide, the more protected the water – but plan to be out before the reef edge starts to break.

Rips form only in larger seas. The eastern side is more exposed and for experienced divers. Diveable year-round; autumn is best.

Enter from the western end of the beach, swim out over the seagrass and weed flats at 2–4 m and follow the western reef seaward, dropping to 8–12 m off the point. Work along the reef edge with the rock on one shoulder, turn at half gas, and return inside the bay across the seagrass, where rays and Port Jackson sharks lie. Exit on the beach where you entered.

Snorkellers stay inside the bay over the weed and rock pools.

No dive shop or dedicated dive charter is based on Phillip Island. Sites are dived by Melbourne clubs (VSAG, Melbourne University Underwater Club, Frankston/Peninsula clubs) and private boats launched at Newhaven or Rhyll; Mornington Peninsula shops (Dive Victoria Group, Portsea; The Scuba Doctor, Rye) run occasional Phillip Island days. Ocean Adventures Phillip Island (Cowes) runs seal-snorkel tours only.

Kitty Miller Bay is the island's most used shore dive and snorkel spot and features on club shore-dive calendars.