Laguna de Bay is the largest lake in the Philippines and the third largest in Southeast Asia, stretching about 90 kilometres from east to west. Los Baños occupies a strip of the south shore, and the lakefront here is accessible by road and on foot. In the late afternoon, the light on the lake is spectacular — the Laguna de Bay sunset is considered one of the better vantage points in the region.
The lake is heavily used for aquaculture (fish pens are visible throughout), and the shoreline in the populated areas is not pristine, but the open water views are wide and the scale impressive. Bangka (outrigger canoe) fishing boats are visible at all hours. The lake influences the local climate, moderating temperatures on the south shore and producing frequent afternoon fog.