If you visit Guam, it is quite likely that Tumon Bay will be the place you stay. This large sandy beach, about 1,5 miles long, is filled with resorts, restaurants and bars. Fringed by a large and stunning lagoon, ideal for beginners, and offering a stunning reef drop-off to experienced snorkelers, it is the most accessible (and the busiest) snorkeling spot in the island.

View on Tumon Bay's coral reef, Guam snorkeling

How to get there?

Located on the West side of the island, a 10-minute drive from the airport ($25-30 by taxi), Tumon Bay is the main seaside resort in Guam, where most of the luxury hotels are concentrated.

Water entrance

You can enter the water anywhere along the beach, but if you plan to explore the reef drop-off, you should enter the water approximately in front of the channel.

Tumon Bay snorkeling map, Guam

Exploration

This spot can be divided into two areas: the vast shallow lagoon, starting from the beach and some 400 yards wide, ideal for beginners, and the reef drop-off area, that should be only explored by the most experienced snorkelers.

The lagoon

Tumon Bay lagoon is an ideal place for a first time snorkeling. The water is warm, clear and shallow (↕2-4ft/0.5-1m), with absolutely no currents and no waves. The seabed is mostly sandy with scattered coral areas, which grow denser as you move closer to the reef. Although the lagoon is shallow and there is little coral, you can still observe several species of fish, including butterflyfish, triggerfish, Moorish idols and damselfish. The lagoon can be explored at almost any time of year, since the waters are particularly well sheltered.

Double-saddle butterflyfish at Tumon Bay, Guam snorkeling

The drop off

The barrier reef and its drop off are located about 400 meters from the shore. You can identify this area from the beach because of the waves breaking there (a white line). On your way to the reef edge, 50 yards before the barrier, the coral becomes so dense that it’s difficult to go further, but some channels allow you to go out on the other side of the reef. On the drop-off (↕3-12ft/1-4m), which plunges abruptly down toward ocean’s depth (↕100ft/30m), the seabed is exceptional. In the presence of the density and variety of the marine life here, you will not know which way to look. Swim along the reef edge and, here and there, you will surely spot shoals of surgeonfish, emperor and royal angelfish meandering alone, huge triggerfish, and maroon clownfish playing in their anemone.

Fire clownfish on Tumon Bay reef drop-off, Guam snorkeling

Please keep in mind that only the more experienced snorkelers can adventure in this area, and only when the sea conditions permit. Be careful and postpone your swim if sea conditions are poor, since this spot can be extremely dangerous. Always keep at a safe distance from the channel, as boats and jet skis use it to reach the open ocean. As the spot is extensive and particularly pleasant, you should protect yourself from the sun since you are likely to spend longer in the water than you first planned.

Restaurants and accommodation

There are a dozen upmarket hotels on the beach, facing the lagoon. In this area, along Pale San Vitores Road, you will find a large number of places to eat and shop.

Species you may spot while snorkeling Tumon Bay
COMMON NAME SCIENTIFIC NAME ABUNDANCE FISHBASE WIKIPEDIA
Whitetail dascyllus Dascyllus aruanus  
Double-saddle butterflyfish Chaetodon ulietensis  
Chevron butterflyfish Chaetodon trifascialis  
Ornate butterflyfish Chaetodon ornatissimus  
Teardrop butterflyfish Chaetodon unimaculatus  
Tomato clownfish Amphiprion frenatus  
Yellow tang Zebrasoma flavescens  
Lined surgeonfish Acanthurus lineatus  
Blue sea star Linckia laevigata  
Lagoon triggerfish Rhinecanthus aculeatus  
  • Level required Beginner
  • Maximum depth3ft/1m in the lagoon, 100ft/30m on the drop-off
  • Water entranceEasy, from a sandy beach
  • LifeguardYes
  • Visitor numbersHigh
  • Access costsFree
  • Restaurants nearbyYes
  • Public toilets & showersNo

MAP Spot

These snorkeling spots are accessible to beginners and kids. You will enter the water gradually from a beach, or in a less than 3ft. deep area. The sea is generally calm, shallow, with almost no waves or currents. These spots are usually located in marked and/or monitored swimming areas. It is not necessary to swim long distances to discover the sea life.

This level only apply when the spot experiences optimal sea and/or weather conditions. It is not applicable if the sea and/or weather conditions deteriorate, in particular in the presence of rough sea, rain, strong wind, unusual current, large tides, waves and/or swell. You can find more details about the definition of our snorkeling levels on our snorkeling safety page.