Egghead

Egghead is an island in the New World belonging to the World Government, which houses the laboratory of Dr. Vegapunk. It is said to be "500 years in the future".

It is the main setting of the Egghead Arc.

Geography
Egghead appears to be a relatively small island dotted with trees, with its most notable feature being a giant egg-shaped structure that towers above the clouds.

Climate
According to Nami, Egghead is a winter island. The waters surrounding Egghead feature freezing winds, icebergs and strong currents that even Jinbe, a fish-man helmsman, admitted were too powerful for him to navigate through properly.

Bizarrely, warm eddys that rise several meters upwards (to the point of resembling a waterspout) are found in this area, implying the existence of high-temperature water coming from somewhere.

Egghead Arc
A Marine ship sailed to Egghead after Koby was abducted by the Blackbeard Pirates.

Trivia

 * Egghead is derogatory slang for smart or studious people.