The Pasig River system runs through five cities and four municipalities (Figure III.2) and
connects two large, important bodies of water; Manila Bay in the west is the country's
main port of maritime trade and travel and Laguna de Bay in the east is the largest
freshwater lake in the country and connects 30 suburban towns to the metropolitan
centre. Before the colonial period, the Pasig River was the main point of entry for
international trade into what is now the City of Manila. Advancements in land
transportation have changed the landscape considerably.