Annalong Harbour Slipway provides a sheltered shore entry point located just north of the main harbour entrance. This site is suitable for beginners, offering a shallow dive experience with depths ranging from 1 to 2 metres and an average depth of 1 metre. Divers typically spend 45 minutes exploring the area, which features both artificial and natural reef structures. Conditions are generally mild, though divers should remain aware of potential surge, entanglement risks, and local boat traffic. Facilities available at the site include parking, toilets, showers, and a cafe. The location is also suitable for snorkelling, with a rating of 3 out of 5.

Arthur's Port is a historic rocky cove located north of Annalong Harbour. This site features a combination of reef structures and kelp forests, characterised by kelp-covered gullies. Access is via the shore, and the site is suited to intermediate snorkellers. Conditions include moderate currents and potential surf, requiring careful planning. Water temperatures are cool, ranging from 8°C to 15°C throughout the year, and are not considered comfortable for prolonged swimming. Parking is available for visitors. Due to the nature of the environment and the presence of strong currents and surf, this location is best suited for those accustomed to cold-water conditions.

Janet's Rock in Strangford Lough offers a secluded sandy cove and rocky outcrops that form natural pools. This site is suitable for intermediate snorkellers who can navigate the rocky seabed and kelp forests. Access is via the shore. Water temperatures at this location vary throughout the year, ranging from 8C in March to 15C during the summer months from July to September. Due to the nature of the terrain and the requirement for shore entry, this site is best suited for those with previous snorkelling experience.

Annalong Rock Pools, located in the Mourne Mountains, offer a freshwater snorkeling experience within a series of natural pools. The largest pool provides sufficient depth for full submersion, set against a backdrop of granite boulders. The water is peaty in appearance. Access is via the shore, and the site is suitable for beginners. Water temperatures fluctuate throughout the year, ranging from 8C in March to 15C during the summer months of July, August, and September. As a shore-based activity, it is rated 3 out of 5 for snorkeling.

Maggie's Leap is a dramatic chasm located in the cliffs south of Newcastle within Strangford Lough. This site features vertical underwater walls adorned with sponges and anemones. Access is primarily by boat or kayak, and the location is suited for advanced snorkellers due to the nature of the terrain. Water temperatures in the area fluctuate between 8C and 15C throughout the year. The site is noted for offering some of the best visibility in the region, providing a clear view of the cliff topography and the sessile marine invertebrates that colonise the rock faces.

Bloody Bridge Coastal Entry is a rugged site where the Mourne Mountains meet the Irish Sea. The shoreline features deep rock fissures and platforms that form natural channels suitable for snorkeling. Access is via a short hike along the coastal path. Water temperatures at this marine site vary between 8C and 15C throughout the year. The habitat supports a variety of temperate marine life, including various reef fish and invertebrates typical of the region. Due to the nature of the rocky entry and coastal conditions, this site is best suited for intermediate snorkelers.

Bloody Bridge Rock Pools, located where the mountains meet the sea in Strangford Lough, offer a unique snorkelling environment within granite basins. The site features deep river pools and rock slides as the river flows toward the Irish Sea. Snorkellers should be aware that conditions vary, and the site is best suited for those with intermediate experience. Access is via the shore. Water temperatures fluctuate throughout the year, ranging from 8C in March to 15C during the summer months. The topography is defined by the dramatic granite formations and the rushing river water.

Derryoge Point is a rugged, rocky stretch of coastline located south of Kilkeel. The site features a classic Mourne Coast underwater landscape defined by numerous deep gullies and submerged boulders. Snorkellers can explore these varied rock formations, which provide a habitat for a range of temperate marine life and invertebrates. Access to the water is via the shore. Conditions at this site vary, with water temperatures ranging from 8C to 15C throughout the year. Due to the nature of the terrain and potential conditions, this site is best suited for intermediate snorkellers.