Dive Site: C-58 Wreck (USS Harlequin / ARM DM-20)

Dive site facts: C-58 Wreck (USS Harlequin / ARM DM-20)

Depth

18–26 m (60–85 ft)

Current

Moderate to strong (drift)

Visibility

10–25 m (33–80 ft)

Water temperature

26–29 °C (79–84 °F)

Entry

Drift / negative entry

Level

Advanced

Dive type

Wreck

Region / port

Isla Mujeres / Cancún, Mexico

Coordinates

21.7375° N, 97.1273° W

Conditions & Currents

The C-58 Wreck is known for its moderate to strong currents, which can be present year-round in the channel between Isla Mujeres and the mainland. Divers often experience drift conditions, and a descent line is not always available, requiring all divers to enter the water and descend simultaneously. This makes it an advanced dive, demanding proficiency in current diving and buoyancy control. Surge is typically not a significant factor at this depth, but water movement around the wreck can be dynamic. Visibility generally ranges from 15 to 30 meters (50 to 100 feet) but may be reduced directly around the wreck due to particles stirred by currents. There are no notable thermoclines mentioned. The challenging current conditions are a key reason for the seasonal return of eagle rays to this area.

Marine life & sighting chances

Black grouper

common

Great barracuda

common

Schooling jacks

common

Nurse shark

occasional

Hawksbill turtle

occasional

Eagle ray

December–March · common

Moray eel

occasional

Manta ray

occasional

Crab

occasional

Dive profile & how the dive runs

Diving the C-58 Wreck typically involves a drift entry due to strong currents, often without a fixed descent line, requiring divers to descend quickly and in unison. The stern, the larger section of the wreck, is usually the primary focus, offering extensive penetration opportunities through its open cargo hold and various rooms. Divers can explore the main deck and superstructure, which are encrusted with corals. The bow section lies approximately 100 meters (300 feet) down current from the stern, resting on its port side, and can be explored as a second part of the dive if air consumption and current conditions permit. Dive depths typically range from 18 to 26 meters (60 to 85 feet). Safety stops are conducted in the blue water at 5 meters (15 feet) for 3 minutes, often while drifting, before surfacing for boat pick-up.

Underwater photography

The C-58 Wreck offers diverse photographic opportunities, from wide-angle shots capturing the expansive wreck and its hurricane-induced breaks to macro shots of smaller life hiding within the structure. A wide-angle lens is ideal for showcasing the full scale of the 56-meter wreck, especially the split sections and penetration points, and for capturing large schooling fish or passing pelagics like eagle rays. Due to the depth and potential for reduced visibility, external strobes are highly recommended to bring back color and clarity. Pay attention to buoyancy, especially during wreck penetration, to avoid stirring up silt. When photographing marine life, maintain respectful distance and observe their natural behavior. The wreck's hard corals and sponges provide excellent foreground elements for dramatic compositions.

Combine with nearby dive sites

• MUSA Underwater Museum

  The MUSA Underwater Museum (Museo Subacuático de Arte) is an extraordinary subaquatic art installation located between Cancún and Isla…

• Manchones Reef

  Manchones Reef, nestled in the protected Bahía de Mujeres off Isla Mujeres, is a renowned dive site celebrated for its calm conditions and…

• Juan Escutia C-56

  The Juan Escutia C-56 is a popular shipwreck dive located in the Puerto Morelos Reef National Park, approximately 15 minutes by boat from…

Getting there & logistics

Diving the C-58 Wreck typically departs from Isla Mujeres or Cancún. Isla Mujeres is reached by a 20-minute Ultramar ferry from Puerto Juárez. Dive trips are usually day trips, with the wreck being a 25- to 40-minute boat ride from either departure point. A typical itinerary often combines the C-58 with another wreck, such as the C-55, or a nearby reef, although the challenging nature of the C-58 often makes it a dedicated advanced dive. Park fees are usually included in the dive package. Divers should ensure they have their Advanced Open Water certification and recent dive experience, particularly with currents. Group sizes are often kept small, around 4-5 divers per guide, due to the challenging entry and conditions.

Safety & environment

Safety at the C-58 Wreck is paramount due to its depth, strong currents, and wreck penetration opportunities. The nearest recompression chamber is located in Cancún. Divers must carry valid dive insurance that covers recompression therapy and emergency evacuation, as medical evacuations typically involve boat transfer to the mainland. Site-specific hazards include potential for rapid descent/ascent due to currents, entanglement within the wreck, and disorientation during penetration. All divers must be Advanced Open Water certified, and experience with currents and wreck diving is highly recommended. Always dive with a reputable operator, follow your dive leader's instructions, maintain excellent buoyancy control, and carry appropriate safety equipment, such as a surface marker buoy. Penetration should only be attempted by divers with proper wreck specialty training and guided by professionals.

Who it suits, and who it doesn't

FAQ

C-58 Wreck (USS Harlequin / ARM DM-20) FAQ

Liveaboards diving C-58 Wreck (USS Harlequin / ARM DM-20)

These liveaboards may visit C-58 Wreck (USS Harlequin / ARM DM-20) on selected itineraries, the exact dive sites depend on departure, weather and conditions.

Nautilus Explorer

Mexico

25 guests45 m

Valentina

Mexico

20 guests38 m

Rocio del Mar

Mexico

20 guests34 m

Nautilus Under Sea

Mexico

19 guests32 m

Nautilus Belle Amie

Mexico

32 guests45 m

Quino del Mar

Mexico

20 guests36 m

Nautilus Gallant Lady

Mexico

12 guests35 m