A "viewing platform" is a designated area or structure that allows you to observe or see something from a higher perspective or vantage point. Full definition
An open - air viewing platform at the rear of the train brings the spectacle even closer and is the ideal spot from which to take photos. (greatrail.com)
There is viewing platform in the heart of the colony that lets you enjoy the birds from up close. (belizescuba.com)
This walk provides a number of wildlife viewing platforms and photo opportunities. (visitotways.com)