The Cremer was a 4,600-ton steel ship built in the Netherlands in 1926 that ran aground on St Bees Island in September 1943, during the Second World War. The Marine Life Network lists her remains near Grimston Point on the north coast of the island in 2–10 m, making this a shallow, accessible wreck for divers with a boat. The hull has broken up over eight decades, but the engine area is mostly intact: two engines, each about 8 m long, and a propeller shaft remain as the centrepiece of the dive.

Around them lie plates and frames colonised by marine growth. Brown sweetlips and honeycomb grouper shelter in the structure, and turtles are regular visitors. Conditions are typical of the Mackay islands.

The site is protected except from south-easterly seas, but current runs along the cliff face, visibility is variable and the remains are often covered in sargassum weed, especially in the warmer months. Slack water on a neap tide in the cooler season gives the best chance of a clear view. Nearby crevices known as the Keswick Caves have recently been explored by a local club and can be combined with the wreck.

No operator runs trips here, so it is a site for private boats and club divers from Mackay. Wartime wrecks should be treated as historic sites – leave everything in place. Precise coordinates are not published in the sources reviewed.

Local club divers in Mackay are the best source of marks and of current information on the wreck's state after recent cyclones.

Keswick and St Bees islands lie in the South Cumberland group roughly 30–35 km north-east of Mackay. A passenger ferry/barge service runs to Keswick Island from Mackay (about 1 hour), landing near Connie Bay; there are also light-aircraft flights. Private boats launch at Mackay Harbour or Mackay Marina (Mackay Harbour boat ramp, Slade Point) and cross in about 45–70 minutes depending on conditions, passing Slade Point and Flat-top Island.

Egremont Passage separates Keswick from St Bees and runs strong tides. There is no dive shop on the islands – bring all gear and fills from Mackay. The Cremer lies near Grimston Point on St Bees' north coast; approach by boat and anchor on sand clear of the remains.

Mackay has the largest tidal range on the Great Barrier Reef coast (springs exceed 6 m), so tidal streams around the Cumberland Islands and in passages such as Egremont Passage are strong and visibility is closely tied to the tide – dive neap tides at slack water. The south-east trades (15–25 knots April–September) make crossings rough; the calmest windows are the build-up months (September–December) and winter lulls. Visibility is typically 5–12 m inshore, often worse after wind or wet-season rain (January–April) from the Pioneer River and local creeks.

Marine stinger season (box jellyfish and Irukandji) runs roughly November to May – wear a full-length stinger suit or wetsuit with hood and gloves, carry vinegar. Cyclone season November–April; tropical lows and cyclones can close sites and damage coral (TC Yasi 2011, TC Debbie 2017). Cyclone Hamish (2009) and Cyclone Debbie (2017) affected reefs in the region.

The site is protected except from south-easterly seas; current runs along the cliff face. Summer sargassum covers the wreck.

Descend near the engine area, examine the two 8 m engines and the propeller shaft at 5–10 m, then explore the rest of the scattered remains. Stay aware of current along the cliff and return to the anchor at slack water.

No regular dive-charter operator currently runs scheduled trips in the Mackay region; divers use private boats, club trips (local dive clubs) and occasional charter boats from Mackay Marina. Nearest dive shops and fills in Mackay.