The Niagara II is a shipwreck and artificial reef located in Big Tub Harbour, Lake Huron. Resting at depths between 10 and 40 metres, this site is suited for intermediate divers with appropriate wreck certification. The wreck features an overhead environment that requires careful navigation. Divers should expect cold water temperatures, typically ranging from 4 to 7 degrees Celsius at depth, with significant thermoclines present. Visibility varies from 5 to 20 metres. Access is by boat only, and divers must remain aware of mild to strong currents. Due to the consistently cold conditions, a drysuit is strongly recommended for all dives.

Dunks Bay in Big Tub Harbour provides a sandy beach entry, offering a more accessible alternative to the rocky coves found elsewhere in Fathom Five National Marine Park. This site is suitable for beginner snorkellers due to its shallow nearshore waters. Conditions are generally mild, though the freshwater environment of Georgian Bay remains cold throughout the year, with temperatures ranging from 2C to 20C. A wetsuit is recommended for comfort. Divers and snorkellers should be aware of potential surf and the risks associated with cold water. Parking is available for visitors. Species recorded around this area include round goby, snails, lake trout, American crayfish, pike, common carp, and small mouth bass.

The Caroline Rose is a wooden schooner resting on the floor of Lake Huron in Big Tub Harbour. This wreck site sits at depths ranging from 10 to 17 metres, with an average depth of 12 metres. Divers experience mild currents and visibility typically between 5 and 10 metres. The vessel offers a well-defined structure for intermediate divers to explore, though the wooden construction presents specific entanglement hazards. Due to water temperatures fluctuating between 2 and 20 degrees Celsius, appropriate thermal protection such as a drysuit or thick wetsuit is essential for all dives. Access to this site requires a boat.

Tobermory HBC is a shallow wreck dive located in Big Tub Harbour, Canada. Resting at an average depth of 6 metres, the site is accessible via a shore entry and features mild currents, making it suitable for beginner divers. Visibility is excellent, often reaching 30 metres. The site offers a 40-minute typical dive duration, though divers must remain aware of boat traffic on the surface and potential entanglement hazards within the wreck structure. Water temperatures fluctuate significantly throughout the year, ranging from 2°C to 20°C, with thermoclines common. Thermal protection is required for all dives.

The Tugs in Big Tub Harbour consists of two historic wooden tugboat wrecks resting in shallow freshwater. Located 50 metres from the shore, the site is accessible via a shore entry and is well-suited for beginner divers. The wrecks lie at depths between 5 and 12 metres, with an average depth of 8 metres. Divers typically experience mild currents and visibility ranging from 5 to 15 metres. Water temperatures fluctuate significantly throughout the year, ranging from 1 to 19 degrees Celsius. Due to the location within an active harbour, divers must remain vigilant regarding boat traffic. Facilities at the site include parking, toilets, and changing rooms.

The Tugs in Big Tub Harbour consist of four small steam tugs resting in shallow freshwater. This site is accessible via a shore-side wooden deck, making it suitable for beginners. The Alice G is the most intact vessel, featuring a visible engine and boiler. Depths range from 3 to 12 metres, with an average of 6 metres. Visibility typically spans 12 to 24 metres. Conditions include mild currents and water temperatures that vary from 1 to 19C. Divers and snorkellers should remain aware of boat traffic in the harbour. Facilities at the site include parking, toilets, and changing rooms.

Tobermory, located in Ontario's Georgian Bay, provides shore-based reef diving in shallow water. The site is accessible year-round directly from the shore, making it a convenient option for divers who prefer to avoid boat entries. While conditions vary, the site is generally suitable for beginners who can move at their own pace. Divers should wear thick-soled boots to protect their feet from sea urchins during entry. Be aware that moderate currents can occur, and visibility may shift depending on weather and the time of year. The habitat supports a variety of temperate reef fish and invertebrates typical of the region.

The Anchor is a freshwater wreck and reef site located in Big Tub Harbour, Lake Huron. Divers can explore the structure at depths between 21 and 22 metres. The site offers visibility ranging from 10 to 30 metres and features a mild current, making it suitable for intermediate divers. Shore entry provides straightforward access, with parking and toilets available on site. Due to the nature of the wreck, there is a risk of entanglement; divers should maintain awareness of their positioning. Water temperatures fluctuate significantly throughout the year, ranging from 1 to 19 degrees Celsius, and thermoclines may be present.