(Laguna Copperplate Inscription, 900 AD), and later by "Pulilan" (Vocabulario de la lengua tagala, 1613. Pila, Laguna). Currently, the lake is often incorrectly called "Laguna Bay," including in government websites, or "Laguna Lake", which is used by the Laguna Lake Development Authority. Geography Laguna de Bay is a large shallow freshwater body in the heart of Luzon Island with an aggregate area of about and a shoreline of . It is considered to be the third largest inland body of water in Southeast Asia after Tonle Sap in Cambodia and Lake Toba in Sumatra, Indonesia. Laguna de Bay is bordered by the province of Laguna in the east, west and southwest, the province of Rizal in the north to northeast, and Metropolitan Manila in the northwest. The lake has an average depth of and its excess water is discharged through the Pasig River. The middle part of Laguna de Bay between Mount Sembrano and Talim Island, is the Laguna Caldera believed to have been formed by two major volcanic eruptions, around 1 million and 27,000–29,000 years ago. Remnants of its volcanic history are shown by the presence of series of maars around the area of Tadlac Lake and Mayondon hill in Los Baños, Laguna, another maar at the southern end of Talim Island, and a solfataric field in Jala Jala. Islands Known lake islands include Talim, the largest and most populated island on the lake; Calamba Island, which is completely occupied by the Wonder Island resort in Calamba, Laguna; Cielito Lindo, a privately owned island off the coast of mainland Cardona, Rizal; Malahi Island which used to be the site of Maligi Island military reservation, near the southern tip of Talim; the nearby islands of Bonga and Pihan, also in Cardona; and Bay Island off the coast of Bay, Laguna, which is closely associated with the precolonial crocodile-deity myths of that town. Tributaries The lake is fed by of catchment areas and its 21 major tributaries. Among these are the Pagsanjan River which is the source of 35% of the Lake's water, the Santa Cruz River which is the source of 15% of the Lake's water, the Marikina River (through the Manggahan Floodway), the Mangangate River, the Tunasan River, the San Pedro River, the Cabuyao River, the San Cristobal River, the San Juan River, the Bay, Calo and Maitem rivers in Bay, the Molawin, Dampalit and Pele rivers in Los