Sketrick Island (Castle Side) offers a sheltered snorkelling environment located in Strangford Lough. The site features a combination of natural reef and artificial structures, including the stone remains of Sketrick Castle near the causeway. With depths ranging from 1 to 8 metres and an average of 4 metres, it is suitable for beginners. Access is via a shore entry approximately 20 metres from the land. Conditions include mild currents, though users should be aware of the potential for strong currents in the area. Visibility typically ranges between 2 and 5 metres. Facilities at the site include parking, toilets, showers, changing rooms, a rinse station, and access to air fills and guided tours.

M.Y. Alastor is a wreck site located in Strangford Lough, United Kingdom. The wreck lies at depths ranging from 13m to 23m, with an average depth of 20m. Access is via a shore entry from the small beach area alongside Ringhaddy Quay, situated approximately 80m from the site. Due to strong currents and variable visibility between 1m and 10m, this site is suited for intermediate level divers and snorkellers. Snorkellers may follow a guide cable in shallower sections between 5m and 10m to explore the structure. Water temperatures fluctuate throughout the year, ranging from 9C in late winter to 15C in late summer.

The Alastor is an almost intact yacht resting upright on the seabed in the middle of Ringhaddy sounds. Located 90 metres from the shore, the wreck is accessible via a shore entry from the end of the pier at Ringhaddy, where a rope leads to the site. The wreck features open sections that are accessible to divers. Depths at the site range from 20 to 25 metres, with an average of 23 metres. Conditions include moderate currents and visibility ranging from 2 to 10 metres. Due to the depth and variable visibility, this site is suitable for beginners who are comfortable with these specific environmental conditions.

Long Sands Rock Pools in Strangford Lough feature significant rocky outcrops along the southern stretch of the beach. These formations create deep pools accessible at mid-to-low tide, providing a sheltered environment suitable for beginner snorkelers. The site functions as a natural aquarium for observing intertidal life in shallow water. Water temperatures at this marine site fluctuate between 8C and 15C throughout the year. Species recorded around this area include harbour seals, grey seals, curled octopus, catsharks, squat lobsters, common lobsters, gurnards, sea slugs, wrasses, compass jellyfish, grey triggerfish, orange-clubbed nudibranchs, skates, and giant jellyfish.

Lime Kilns is a shore-entry dive site located in Strangford Lough, situated directly below the historic 19th-century lime kilns at the northern end of Long Sands. The underwater topography consists of a rocky substrate interspersed with kelp forest patches, providing structural diversity compared to the surrounding sandy areas. Divers can expect depths ranging from 1 to 10 metres, with an average depth of 5 metres. Conditions are variable, with visibility typically between 3 and 10 metres and mild currents. The site is suitable for intermediate divers and offers a moderate experience for snorkellers.

Ballywalter Harbour Bay is a sheltered site located immediately south of the working harbour jetty in Strangford Lough. The topography consists of a mix of reef, artificial reef, and wall structures. This shore-entry site is suitable for beginners, with depths ranging from 1 to 5 metres and an average depth of 3 metres. Divers and snorkellers can expect mild currents and visibility between 3 and 8 metres. Water temperatures fluctuate between 8C and 15C throughout the year. Facilities available at the site include parking, toilets, and a cafe. Hazards to be aware of include surf and currents.

Dully Beach in Strangford Lough features a natural offshore reef that shelters the shoreline from Irish Sea swells. This reef creates a protected, shallow environment suitable for snorkeling at depths between 0 and 10 metres. Access is via a shore entry, and the site is generally suited for beginners. Conditions are characterised by mild currents, though snorkelers should be aware of potential hazards including surf, rip currents, and entanglement. Water temperatures are cool, ranging from 8C to 15C throughout the year, requiring appropriate thermal protection for those spending time in the water. Parking and toilets are available at the site.

Skullmartin Rocks is an offshore reef located 1609 metres from the shore in Strangford Lough. The site is identified by an 11-metre beacon known as the Perch. Topography consists of dramatic bedrock outcrops interspersed with shell gravel beds. Due to the location, this site requires boat access and is suitable for advanced divers only. Conditions are characterised by strong currents, which are a primary hazard for those visiting the area. Water temperatures fluctuate between 8C and 15C throughout the year. While the site is primarily a dive location, it holds a snorkel rating of 4 out of 5.