The Nalon is a coastal minesweeper of the MSC-139 Bluebird class, resting as a wreck in the waters of Cartagena. This advanced dive site sits at depths ranging from 28 to 35 metres, with an average depth of 30 metres. Access is strictly by boat. Divers encounter mild currents and visibility averaging 12 metres. Due to the depth and the nature of the wreck, hazards include nitrogen narcosis and overhead environments. Species recorded around this area include common octopus, European common cuttlefish, Mediterranean moray, wrasses, bream, and scorpionfish. The site is suited for experienced divers capable of managing deep wreck penetration and potential entanglement risks.

Bajo De Emilio is a submerged pinnacle and reef system located off the coast of Cartagena, Spain. The site features a ridge rising from a base depth of 26 to 32 metres up to a shallow peak at 14 metres. Divers access this site exclusively by boat. Conditions are variable, with currents that require intermediate diving skills. The topography includes a monolith dedicated to a local diver. Species recorded around this area include common octopus, Mediterranean moray, conger eel, scorpionfish, and various wrasses and bream. Due to the depth and potential for strong currents, this site is best suited for experienced divers comfortable with deep-water environments.

Cabezo del Mojón is a prominent rock formation marking the border between Cartagena and Mazarron. This marine site features a diverse topography consisting of vertical walls and numerous underwater cavities. Divers can expect depths ranging from 3 to 16 metres, with an average depth of 10 metres. The site is accessed from the shore and is suitable for intermediate divers. Conditions include moderate currents and potential surf, requiring careful entry. Facilities available at the site include parking, toilets, showers, and first aid. Typical dives last approximately 45 minutes, and the site is also well-suited for snorkelling.

Playa del Mojón is a shallow shore-entry reef located in Cartagena, Spain. The site maintains a consistent depth of 5 to 7 metres, making it suitable for beginner divers. The topography features beds of Posidonia seagrass, which provide habitat for various marine life. Divers should be aware that entry involves navigating a surf and shore break, and conditions can include strong currents. Water temperatures range from 15C to 27C, often requiring a wetsuit. Facilities available at the site include parking, toilets, showers, a rinse station, and first aid. Species recorded around this area include wrasses, bream, common octopus, and European common cuttlefish.

Cala del Faro is a protected cove near Cartagena, Spain, offering a sheltered environment suitable for beginners. The site features a seabed composed of sand and posidonia seagrass, with rocky formations extending from the mountain to depths of 2 to 10 metres. With an average depth of 6 metres, it is frequently used for introductory diving sessions and training courses. Access is by boat, and the site is noted for mild currents and visibility reaching 15 metres. Species recorded around this area include wrasses, bream, common octopus, and various Mediterranean marine life. Divers should be aware of sea urchins present in the rocky areas.

Escollera del Puerto in Cartagena is a shore-entry site featuring a combination of muck substrate and artificial reef structures. Divers can explore depths ranging from 5 to 13 metres. The site experiences moderate currents, making it suitable for beginners with an open water certification. Due to its location in a working harbour, divers must remain alert for boat traffic and potential entanglement hazards from lines or debris near the structures. Visibility at this site varies, so conditions should be checked on the day. Nearby facilities include a dive shop offering air fills and parking.

Freo is a drift dive located on the crest of an underwater mountain near Cartagena, Spain. The site features a depth range extending from 26 metres at the summit down to 42 metres. Due to the strong currents and significant depth, this site is strictly for advanced divers. Access is exclusively by boat. Divers should be prepared for challenging conditions and manage their depth profiles carefully throughout the dive. The site offers various navigation routes depending on diver experience and certification levels.

Cueva del Agua in Cartagena is a shallow reef and drop-off site accessible from the shore. The topography features a channel leading from the mainland to a small, flat island, which snorkelers can circumnavigate. Depths at this site range from 1 to 10 metres, with an average depth of 5 metres. Conditions are generally calm with mild currents, making it suitable for beginners. Facilities available at the site include parking, toilets, showers, changing rooms, and a rinse station. Divers and snorkelers should be aware of potential hazards including sea urchins and sharp coral when navigating the area.