Gainesville, Georgia.
Gainsville is chicken capital of the world.
Wichita KS
The city of Walla Walla in Washington State calls itself the onion-growing capital of the world. It has a long history of onion farming and produces a large portion of the world's sweet onions.
Poultry
Yes. There are various types of poultry all around the world. Do you have a specific question?
Yes. Mexico is the 5th largest poultry producer in the world (2012).
Smithfield
The United States is the largest poultry meat producer in the world.
Waynesboro is the bird dog captial of the world.......or so they say.
It is a borough in Chester County near Philadelphia that bills itself as the Mushroom Capital of the World.
The world's second largest island is the island of New Guinea, but the island is split between the countries of Indonesia and Papua New Guinea and does not have a capital city itself. (The capital of Indonesia is Jakarta and the capital of Papua New Guinea is Port Moresby)
The Vatican considers itself to be a neutral country and rarely expresses an opinion about world leaders. They so express opinions about some policies and laws, however.