- Surigao is very rich in nature, in fact mangroves is the major theme in the coastal areas and is the biggest reserved mangrove forest in Mindanao. If you are interested in fishing or spear-fishing you can try to visit the seas along the tuna route. There are so many different kinds of species caught their every year. There are also some caves and tunnels that are half-submerged and can only be accessed during low tides. The city managed to preserved its natural marvel environment through the years.