Library of rooftop open-air infinity pool

Quick answer：

A rooftop open-air infinity pool is a type of swimming pool designed to be installed on the top of buildings, often with a view of the horizon to create a sense of infinity. Infinity pools are characterized by their deep end that seems to drop off into nothing, creating the illusion of an endless body of water. These pools are popular for their aesthetic appeal and the panoramic views they offer. They require careful planning and engineering to ensure structural integrity and safety.