Breaking through the water's surface as we descend into the past. Transporting ourselves to another dimension, a passage of history where time stood still at a specific moment... It's like using a time machine to explore what the sea guards zealously, and which, little by little, becomes part of it.
Wreck diving, exploring the remains of different civilizations swallowed by the waters for various reasons, holds an incomparable allure. Shipwrecks, naval and aerial battles, storms, accidents, and sometimes human intent have scattered remnants across the seabeds of the entire world.
Learning the history of a wreck—its characteristics, crew, cargo, fate, and how it sank to finally rest in the depths—is to understand a bit more about human history through the ages. No words can truly capture the feeling of exploring certain wrecks. You feel like a stranger wandering through its innards, observing the mysteries it holds.
Recognised for their appeal to the vast majority of divers, wrecks are now part of diving routes and immersions in nearly all diving destinations. This doesn’t mean they’re accessible to every diver. Each wreck has specific characteristics we must assess before attempting to visit. These dives, considered higher risk than open-water dives, always require thorough prior planning.
Factors to Consider Before the Dive
a) Historical Context
You can never have too much information. First, gather historical data about the wreck: its mission, route, destination, cargo, crew, construction year, cause of sinking, etc. Anything that provides context and situates what we’re about to see in time. This helps us appreciate the significance of the wreck’s parts and know what to look for inside.
Some wrecks are entirely off-limits due to state or national laws, whether because of their cargo, religious reasons, or regulations protecting archaeological remains. Each country has specific laws, so it’s wise to research, as some are very strict regarding the removal or relocation of wreckage.
b) Individual Wreck Characteristics
Distance from shore. Exact position. Depth of the wreck. Shallowest and deepest areas. Average dive depth. Length and beam dimensions. Wreck position (upright, starboard side, port side, upside down, degrees of tilt...). Sections it’s divided into. General condition. Accessibility. Hazardous or toxic cargo (especially in military wrecks).
Evaluating these details helps determine the ideal gas mix (air, nitrox, etc.), bottom time, and required decompression. We’ll know if multiple dives are needed, the best entry point, and areas to avoid.
Depending on the wreck’s position, it may be easier or harder to get lost inside. Navigating a wreck is disorienting—low light, narcosis (beyond 35-40 metres), and similar interior spaces complicate navigation. Misjudging ascent speed or direction is common when exploring corridors or rooms. Some wrecks are true labyrinths.
Plan maximum bottom time, stops, and total decompression. Chart a route (always from deepest to shallowest), bow to stern or vice versa, marking exploration points. The dive profile should be "square" or "V-shaped," never "sawtooth" with sharp ascents/descents. The side (port or starboard) to explore may depend on current protection.
c) Sinking Zone Characteristics
First, consult nearby dive clubs, guides, divers familiar with the wreck, and local fishermen.
Currents. Water temperature. Typical visibility. Seabed type (mud or silt often means poor visibility). Added hazards like fishing nets snagged on wrecks in trawling zones.
Local marine life. Wrecks are quickly colonised—corals and organisms needing solid substrates cover them in life and colour. Fish also use them as shelter, including large predators attracted by abundant food. Know the species present and be cautious in dark, tight spaces to avoid venomous or biting creatures.
d) Essential Gear for Wreck Diving
As mentioned, this isn’t a standard dive, so gear must be more comprehensive. Start with a durable wetsuit suited to water temperature.
From a drysuit for deep dives to a robust full suit for tropical waters. The wreck’s condition depends on many factors (time, local conditions, sinking cause, materials used...). But all share rusted, sharp metal edges. Wood, the first material to decay, requires caution around splintered areas. Thus, cut-resistant suits and gloves are essential.
The diving apparatus. A standard BCD works for dives around the wreck or at shallower depths. A technical BCD offers better buoyancy control inside wrecks and more D-rings for extra gear (cylinders, torches, reels...).
Gas supply (air/nitrox) and cylinder size depend on dive planning. Two independent DIN/INT regulators are needed, hence twin tanks with dual valves. For tight spaces, use valve guards to prevent accidental shut-offs from ceiling contact.
Underwater, secure all gear—no dangling hoses or items that could snag or cut on rusted metal. The dive computer must calculate decompression for the gas mix used.
Safety Tips
- First-time wreck divers should ideally be accompanied by an experienced guide or diver who knows the wreck well.
- Two sharp knives, with line cutters and serrated edges. (Not too small—they should serve as levers if needed).
- Two torches per diver (25-50 watts).
- A reel with 100 metres of cut-resistant line. Crucial for complex wrecks or poor visibility.
- A safety bottle hung on the ascent line at the appropriate depth for decompression stops.
- Compass. Never rely on a single navigation tool. Inside wrecks, compasses may magnetise and give false readings, but combined with wreck observation and another diver’s guide line, they’re useful.
- For acoustic signalling, tap a knife against metal or your tank, or use market-available devices.
Once Inside
- Nothing inside a wreck is worth risking caution or common sense.
- Maintain good buoyancy to avoid cuts, snags, and silt disturbance.
- Assess wreck stability before entering any space. Ensure exits aren’t blockable—mind hatches and doors.
- Limit narrow-space entry to two divers at a time. Wait your turn.
- Beware internal currents and surge in shallow wrecks—waves create siphon effects inside.
- Many wrecks have loose ropes/cables—stay alert to avoid entanglement.
- Always follow the rule of thirds: one-third gas for exploration, one-third for return, one-third as reserve.
Moments to Savour in Wreck Exploration
Each wreck is unique, but some experiences are common:
- The moment it materialises in the blue as you hover above its structure is breathtaking.
- Descending to the massive, motionless propeller and feeling tiny beside the colossal stern, imagining it powering away.
- Observing backlit deck structures, funnels, or masts.
- Taking the helm inside the wheelhouse.
Above all: be a witness to history. Admire these submerged museums without greed, and always prioritise caution.
