In this contribution to the “Ways of Water” series, Debjani Bhattacharyya examines how the tides of the Hooghly River in Kolkata have been visually represented historically. In doing so, she makes a larger point about how cartographic images of the intermingling of rivers and cities fix this relationship in time and space. Bhattacharyya contrasts representations of the Hooghly in maps with those in almanacs, which capture both the temporal and cosmological meanings and practices as experienced by Kolkata’s residents under colonial rule.