One Greek city-state beginning with the letter "P" is Pella. Pella was the capital of ancient Macedonia and the birthplace of Alexander the Great.
Paris, France
There are only two European countries which start with the letter 'P' and they are Poland and Portugal. However neither of their capital cities (Warsaw and Lisbon) begin with the letter 'P.'
Pasco is a city in Washington State. It begins with the letter P.
Panama City is the largest city in Panama. It is the capital city of Panama.
Phoenix, Plano, Paris, Philadelphia, Potsdam,
Pensacola, Florida is a popular U.S. city starting with P. Reno, Nevada is a popular U.S. city starting with R.
Phoenix, Arizona, the largest state capital by population Phoenix is the capital city in Arizona. Pierre is the capital city in South Dakota. Providence is the capital city in Rhode Island.
Paris, Prague, Panama City, Port Harcourt, Peking (old spelling for Beijing), Pristina. I am sure there are more.
Passaic
Paris, capital of France.
some human names from starting letter p