Matterhorn is a freshwater reef dive located in Lake Thun, Switzerland. The site features a reef structure extending from the surface to a maximum depth of 30 metres. Divers can expect visibility between 5 and 15 metres. Due to moderate currents, this site is suitable for divers with at least an Open Water certification. Cold water is a significant hazard, requiring the use of a drysuit or a thick thermal exposure suit. Facilities on site include a dive shop, air fills, equipment rental, and guided tours. Species recorded around this area include snail, common perch, burbot, barbel, chub, pike, American crayfish, and bullhead.

Stampach in Lake Thun is a demanding freshwater dive site featuring a wall and canyon topography. The site reaches depths of 34 metres, with an average depth of 22 metres. Divers enter from the shore, located 50 metres from the main structures. The environment is characterised by strong currents that can funnel unpredictably through the canyon, requiring careful planning and advanced buoyancy control. Visibility typically ranges between 6 and 10 metres. Due to the significant depth, potential for entanglement, and overhead environments, this site is suited for advanced divers. Facilities at the shore entry point include parking and a rinse station.

Niesen in Lake Thun offers diverse freshwater diving across reef, wall, and muck environments. The site extends from 7 to 46 metres, with deeper sections requiring decompression procedures. Divers should expect mild currents and visibility ranging between 6 and 10 metres. Due to the significant depth and cold water temperatures, which fluctuate between 4 and 24 degrees Celsius depending on the season, this site is suited for intermediate divers with appropriate thermal protection. Shore access is available with parking located at the entry point. Divers should maintain strict awareness of their dive profile and depth throughout the typical 35-minute dive.

Gunten Bad in Lake Thun offers a distinct freshwater diving experience defined by dramatic underwater rock walls and canyons. Divers can expect depths ranging from 15 to 50 metres, with an average depth of 30 metres. The site is accessed via a shore entry and is suitable for intermediate divers. Conditions include mild currents and visibility typically between 5 and 15 metres. Water temperatures are cold, dropping to 4°C during winter months. The site supports night diving and features facilities including parking, toilets, and air fills. Divers should remain aware of the significant depth and potential for entanglement hazards during their 50-minute dives.

Bäregg in Lake Thun offers a distinct freshwater diving experience characterised by underwater rock formations and small vertical walls. The site reaches depths between 20 and 30 metres, with an average depth of 25 metres. Divers enter from the shore for a typical 50-minute dive. Visibility at this site ranges from 5 to 10 metres. Species recorded around this area include snails, common perch, burbot, American crayfish, barbel, bullhead, chub, and pike. Due to the presence of boat traffic, cold water, and variable visibility, this site is best suited for intermediate divers. Parking and toilets are available at the location.

Stampach Ralligen in Lake Thun is an advanced dive site characterised by a steep underwater wall, reef structures, and a canyon. Divers can explore submerged trees located approximately 100 metres from the shore. The site reaches depths of 20 to 30 metres, with an average depth of 25 metres. Conditions include moderate currents and visibility ranging from 6 to 10 metres. A thermocline is present, with temperatures at 20 metres and deeper remaining constant at 5 to 6 degrees Celsius. Due to the depth, cold water, and potential for entanglement, this site is suited for experienced divers. Parking is available for site access.

Längenschachen in Lake Thun offers a gentle, sloping dive profile suitable for beginners. The underwater terrain transitions from stony to muddy, with seagrass beds extending to a depth of 5 metres. Divers typically reach depths between 2 and 15 metres, with an average of 10 metres. Access is via an easy shore entry located 50 metres from the parking area. Conditions feature mild currents and visibility ranging from 3 to 10 metres. The site is also popular with bathers during summer months, requiring awareness of boat traffic and surface activity. Facilities at the site include parking, a cafe, and toilets. Night diving is permitted at this location.

Spiezerberg is a deep freshwater wall and canyon dive located in Lake Thun. The site features topography ranging from 20 to 40 metres, with an average depth of 30 metres. Access is by boat only, and divers should be prepared for cold water temperatures, which remain constant at 5-6°C below the thermocline. Visibility typically ranges between 5 and 10 metres. Due to the significant depth and potential for entanglement on sharp rocks, this site is suited for intermediate divers. Facilities including air fills, showers, and changing rooms are available nearby. Species recorded around this area include snail, common perch, burbot, barbel, American crayfish, chub, pike, rainbow trout, and bullhead.