The "bomb holes" are a series of shallow depressions (20-30' deep) off the village of Piti. The popular story is that they are bomb craters from WW2, but some geologists say they are natural sinkholes caused by collapsed caverns. They are right next to the Fisheye underwater observatory which is a long pier leading out to a submerged viewing room. This area is usually packed with tour buses full of tourists who come here for the observatory and to snorkel and walk all over the reef. It's a protected area so no fishing or collecting is allowed. I dove here on March 1, 2019.
I snorkeled out over the knee-deep bottom towards the bomb holes. Local practice for divers is to wade out near the pier to avoid trampling the sea grass bed that covers much of the surrounding area. I swam out over the sea grass without touching the bottom, but at a lower tide this wouldn't be possible.
I reached one of the bomb holes. The sides were covered with a kind of soft coral. There were some mounds of hard coral on the 20'-deep sandy bottom in the middle.
I swam up to the rim of the crater and headed over the shallow, coral-covered bottom towards the crater that had the Fisheye observatory in it.
There were a few black tip reef sharks swimming around.
Near the observatory there was a walkway set up for some kind of "reef walker" tour.
This dive had the greatest variety and abundance of fish and coral of all the sites I dove on Guam. I did another dive here the next day (to take some video). On the second dive I was diving in the middle of the day (this first dive was in the evening) so the water was busy with snorkelers and divers. I also didn't see any sharks. Maybe it was too early in the day or they were scared away by all the people.
