Nicus Nature is a reef and drift dive site located in the Alssund, part of the Little Belt. The site features a reef profile ranging from 2 to 25 metres, with an average depth of 15 metres. Strong tidal currents define the experience, requiring careful planning around tide tables to ensure safety. Visibility typically fluctuates between 5 and 15 metres. Given the water temperatures of 4 to 15 degrees Celsius, a drysuit is recommended. This site is suited for intermediate divers capable of managing drift conditions. Shore access is standard, though divers should remain aware of surge and swell conditions during entry and exit.

Svendborg Sundbroen in Alssund offers a combination of natural reef and artificial structures suitable for beginner divers. The site features depths ranging from 6 to 12 metres with an average of 6 metres. Divers experience visibility of approximately 5 metres and must contend with moderate currents. Due to the proximity of the navigation channel, boat traffic is a constant hazard, and the use of a surface marker buoy is essential. Water temperatures fluctuate between 4C and 17C, requiring appropriate thermal protection. Parking is available at the site, providing convenient access for shore entries just 5 metres from the shore.

MTB 1 is a motor torpedo boat wreck located in the Alssund strait, Denmark. Resting at a depth of 8 to 10 metres, the wreck is suitable for intermediate divers. Visibility at the site typically ranges from 5 to 15 metres. Divers should be prepared for cold water temperatures, which fluctuate between 4C and 17C throughout the year, necessitating a drysuit or thick wetsuit. Access to the site is by boat only. The area experiences mild currents, though tidal flows in the Little Belt can strengthen, and divers must remain vigilant for active boat traffic in the strait. A surface marker buoy is recommended for all ascents.

The M/F Ærøsund is a scuttled ferry wreck located in the Alssund, Denmark, resting at depths between 6 and 19 metres. Purposefully sunk in 2014 as an artificial reef, the vessel was cleared of hazardous materials to facilitate diver access. The site is situated 550 metres from the shore and requires boat access. Divers encounter mild currents and visibility ranging from 5 to 10 metres. Water temperatures fluctuate between 4C and 15C throughout the year. Due to the nature of the wreck, divers should be aware of potential hazards including entanglement and overhead environments. This site is suitable for intermediate divers, with boat charters and guided tours available.

Knudshoved Ferry Harbour in the Little Belt offers an intermediate dive experience featuring a wreck and artificial reef structures. The site is shallow, with depths ranging from 6 to 8 metres, allowing for extended exploration. Visibility typically varies between 5 and 10 metres. Divers should exercise caution regarding buoyancy to avoid contact with sharp growth on the structures. Access is via shore, though local advice suggests boat entry to avoid surf and rip currents near the shoreline. Divers must remain vigilant for boat traffic when surfacing and monitor local weather reports for current strength. Water temperatures fluctuate between 4C and 17C, necessitating appropriate thermal protection.

Wreck S103 is a boat-access dive site located in the Alssund, Denmark. The wreck rests at depths between 20 and 33 metres, with an average depth of 26 metres. Divers encounter moderate currents and limited visibility of approximately 5 metres, necessitating the use of a torch and a reel. Due to the depth and cold water temperatures ranging from 4 to 14 degrees Celsius, this site is suited for intermediate divers. The environment supports temperate marine life typical of the region, including various reef fish and invertebrates. Divers must manage nitrogen narcosis risks and use a surface marker buoy due to active boat traffic in the strait.

Halskov Rev in the Little Belt is a shore-accessible site featuring a combination of natural reef and artificial structures provided by the bridge piers. Divers typically explore depths between 1 and 7 metres, with an average of 5 metres. The site is characterised by strong currents, requiring careful planning and the use of a surface buoy. Divers should swim against the current at the start of the dive to ensure an easier return. Due to the cold water temperatures, which range from 4C to 19C, appropriate thermal protection is essential to mitigate the risk of hypothermia. Facilities at the site include parking, showers, and a rinse station.

Korsør Gl. Færgehavn is an artificial reef site located in the Little Belt. Divers enter from the shore near the volleyball court and swim approximately 150 metres to reach the ferry berth structures. The site features a tiled bottom, old piles, and remnants of the ferry era, including cavities and fallen bulwark piles. Divers can navigate between beams at the towers southwest of the beach and explore various submerged objects such as shipwrecks and debris. Depths range from 3 to 10 metres with an average of 7 metres. Conditions include mild currents and potential hazards such as boat traffic, entanglement risks, and surf. The site is suitable for intermediate divers and supports night diving.