Stadium
A stadium (plural stadiums or stadia) is a place or venue for (mostly) outdoor sports, concerts, or other events and consists of a field or stage either partly or completely surrounded by a tiered structure designed to allow spectators to stand or sit and view the event.
Pausanias noted that for about half a century the only event at the ancient Greek Olympic festival was the race that comprised one length of the stade at Olympia, where the word "stadium" originated.
Etymology
"Stadium" is the Latin form of the Greek word "stadion" (στάδιον), a measure of length equalling the length of 600 human feet. As feet are of variable length the exact length of a stadion depends on the exact length adopted for 1 foot at a given place and time. Although in modern terms 1 stadion = 600 ft (180 m), in a given historical context it may actually signify a length up to 15% larger or smaller.
The equivalent Roman measure, the stadium, had a similar length — about 185 m (607 ft) - but instead of being defined in feet was defined using the Roman standard passus to be a distance of 125 passūs (double-paces).