Japanese sewer system makes an excellent place to stage a Quake match

That's a normal-sized person on the floor of the place. The storm sewer system underground in Saitama, Japan, is one of the largest in the world and a steady tourist attraction.

Saitama has a population of about 1.2 million, making it the most populous cities in the prefecture. And situated where it is on the coast and Japan being prone to the sea-related disasters as it is, the storm control system is no joke.