Lapet Republic

Lapet Republic (, Rabe Kyōwakoku) is a location that is roughly as big as Meteor City.

Overview
The size of the Lapet Republic is speculated to be as big as Meteor City.

Greed Island arc
The Mafia Hacker uses the Lapet Republic in an explanation to two Mafiosi of the tantamount size of Meteor City.

Trivia
The Lapet Republic is about the size of real-life Tokyo Metropolis (2,187.66 km²) plus Saitama Prefecture (3,798.08 km²) of Japan (approx. 5,985.74 km²/2,311.11 sq. mi.), as noted in Chapter 102 of the manga for reference.