Tokyo Dome is a stadium in Bunkyo Ward, Tokyo that can seat 55,000 people. It hosts all kinds of events from baseball to K-1 and monster truck races. It is also the home of the Yomiuri Giants Baseball team.
Tokyo Dome was built on the site of Korakuen Stadium and was opened first on March 17, 1988.
The name says it all: it is a dome-shape stadium and therefore was quickly nicknamed The Big Egg. The dome itself is an air-supported structure or a flexible membrane that is held up by pressure that slightly higher inside the dome than outside.