The Crystal Clear Waters Of Marbo Cave

Photo of Marbo Cave in Guam

Marbo Cave (a.k.a. Campanaya Cave or Campanaya Spring) is a flank margin cave located at the base of a cliff on the Pacific coast of northern Guam and frequented by locals (Chamorro) and military personnel stationed on the island. It is one of the island’s best known caves with others including Pagat Cave and Fafai Cave.
Currently, eighty percent of the Guam’s drinking water is drawn from the karst aquifer in the limestone plateau in the northern half of the island. Marbo Cave and spring specifically were used as a water source by the Japanese Army during their occupation of the island from 1942 to 1944 and then by the U.S. Army from 1947-1950. The large cement platform in front of the spring provided a base for an electrical water pump. Of note,

While stationed on the island, I visited the cave after taking a detour off of GU-15, a road beginning mid-island and following the eastern coast up to Anderson Air Force Base in the north. Turning off of GU-15, the dirt road eventually leads you to a parking area where you can walk along the island’s beautiful Pacific coast.

Dirt road off of GU-15
View of Guam’s Pacific coast

Instead of following the road all the way to the coast, taking a left brought us to an area where we parked and were able to see the entrance to the cave.

Parking area near the entrance to Marbo Cave
Entrance to Marbo Cave

The cave has a large collapse entrance at the base of a cliff that leads to a room that is approximately 20 meters across and contains a freshwater pool. The caves floor is filled with breakdown except for the concrete platform described above that was used to support the water pump in the World War II era.

The way down into Marbo Cave
The main room with it’s freshwater pool to the left and concrete platform
The freshwater pool in Marbo Cave

The large collapse boulder to the left of the platform separates the cave into two portions, a shallow pool of 2 meters and the deep which is 6 meters deep. At one time it was thought that this was the caves only chamber, though SCUBA investigations have since revealed additional rooms and passages including an 8m long tubular passage that contains an air pocket penetrated with plant roots. Sadly, in 2015 an airmen drowned (article) after attempting to reach this air pocket and back…

At the bottom of the deep pool is another narrow passage that leads to a small room with hundreds of small stalactites that is only accessible via SCUBA.

Extensive passages can be found from the shallow pool end (20 meters +) that are made by collapsed rubble and contain clay and silt deposits. These passages have not been investigated due to the risk of collapse for divers.

Screenshot of Marbo Cave Map by Danko Taborosi from a Technical Report done for the University of Guam

Please note that caving can be a dangerous activity for the inexperienced. If you have an interest in exploring caves, check out a local grotto from the National Speleological Society website so you can connect with experienced cavers in your area who will show you the ropes. Also, remember that caves can be on either private property or government land so please always ensure that you either have permission from the landowner or the proper permits obtained before visiting a cave. While there, remember to…

Take nothing but pictures.

Leave nothing but footprints.

Kill nothing but time.

1 Comment

Leave a Reply

Your email address will not be published. Required fields are marked *