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.

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.

Inner Lees is a shallow marine dive site located within Strangford Lough in the United Kingdom. The site features a consistent depth range of approximately 5 to 6 metres. Conditions at this location vary, with water temperatures ranging from 9C in the late winter and early spring to 15C during the late summer months. Given the shallow nature of the site, it is suitable for divers seeking a relaxed, low-depth experience. Access to the site is typically via boat, though local conditions should be assessed prior to entry.

Ballyhenry Island in Strangford Lough is a small tidal island that provides a shallow snorkeling environment along its boulder-strewn shore. Accessible from the shore, the site is suitable for beginners looking to explore the coastal topography. Water temperatures at this location vary throughout the year, ranging from 9C in the late winter and early spring to 15C during the late summer months. The site is also noted for its rock pooling opportunities at low tide. Due to the tidal nature of the island, visitors should plan their entry and exit times carefully according to the local tide tables.

Inner Lees in Strangford Lough features the remains of a WWII blockship. The bow section of the vessel is a distinct feature that breaks the surface at low tide, making it a shallow site suitable for snorkelers. Access is straightforward from the adjacent shingle beach. Water temperatures at this site vary throughout the year, ranging from 9C in the late winter and early spring to 15C in the late summer and early autumn. Due to its shallow nature and ease of entry, the site is well-suited for beginners looking to explore maritime history in a sheltered marine environment.

Chapel Island Tidal Pool is a deep natural formation situated between Chapel Island and the mainland in Strangford Lough. The site maintains significant depth even during low tide, creating a contained environment for snorkelling. Access is possible via boat or by walking across the seabed during low tide, though the site is best suited for intermediate snorkellers due to the tidal nature of the area. Water temperatures fluctuate between 9C and 15C throughout the year. As a tidal pool, conditions can vary, and visitors should plan their entry and exit according to local tide tables to ensure safe navigation of the surrounding area.

Ballyhenry Bay in Strangford Lough is a sheltered site featuring a well-established Zostera marina seagrass bed. This habitat serves as a nursery for juvenile fish and provides an environment for observing smaller marine life. The site is suitable for beginners and offers shore access for snorkelling. Water temperatures in the bay range from 9C in the late winter and early spring to 15C during the late summer months. As a sheltered location, it provides a manageable environment for those looking to explore the local seagrass ecosystem.

Outer Lees in Strangford Lough is a wreck site featuring the stern section of the Empire Tana. Divers and snorkellers can explore the hull, which is covered in dense kelp forests, sponges, and sea squirts. The site is located 1000 metres from shore and requires boat access. Conditions are variable, with depths ranging from 12 to 18 metres and visibility between 5 and 15 metres. Due to strong currents, down currents, and potential entanglement hazards, this site is suited for intermediate divers. Boat traffic is a common hazard, and the wreck presents an overhead environment. Facilities including air fills, guided tours, and boat charters are available nearby in Portaferry.