This site is at Serena Island, and "Besar" means big or large. The site is a combination of coral, rubble area and a sandy bottom. In the shallow part the nice coral area and some time you can see juvenile barramundi cod also juvenile dotty sweet lips dancing. And going to the middle is the rubble area which is the richest are with critters, this area you can fin a lot of banggai cardinal fish, stick pipe fish and some time ghost pipe fish also can be found. Frogfish also can be found here. In the deep area is the sandy bottom is the place good for finding Octopus like wonderpus, other that you also can find black and blue ribbon eel and devil scorpion fish buried in the sand.