List of largest gatherings in history

This is a list of the largest historic peaceful gatherings of people in one place for a single event.

A method of determining how many people are at an event is the scientific analysis of photographs, video images, or both. Based on the quality of the image, it is possible to do a physical head count or to estimate attendance based on the density of people within similar areas. This permits the estimation of people over large areas or where parts of the image are obscured. An extensive discussion of how images were used to estimate the number of attendees at the Million Man March can be found at the Center for Remote Sensing at Boston University's website.

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