Shelter Nr. 7

'''Shelter Nr. 7''' is a public shelter located in Z-City, built by the Hero Association for the event of attack by Mysterious Beings. Externally, it consists of a giant dome lined with circular vents, which is able to withstand anything from extreme temperatures to missile attacks.

Given its designation, there likely exist other such shelters across the world of OnePunch-Man.

Features
Shelter Nr. 7 very much resembles a sporting venue, with at least seven different entrances meant to accommodate large crowds. It was designed specifically to repel Mysterious Beings, and features biometric authenticators at each entrance to detect any possibly masquerading as human; once the shelter's defense system is active, all entrances are sealed and locked.

The interior of the shelter is largely open space, with rafters overhead installed with sprinklers and speakers to spray negative ions and play classical music, respectively—both meant to calm its likely-panicking evacuees.

However, Shelter Nr. 7 does not feature any restrooms, a rather glaring oversight given its enormous capacity.