That is the name that William Penn gave it when he founded it.
The word 'Philadelphia' is a proper noun, the name of a specific place. A proper noun is always capitalized.
Ronald MacDonald
Riders one the storm!
Philadelphia.
The duration of It's Always Sunny in Philadelphia is 1320.0 seconds.
It's Always Sunny in Philadelphia was created on 2005-08-04.
Ronnie Laws -- Always There from album Pressure Sensitive
Forever Young by alphaville
Charlie Kelly - It's Always Sunny in Philadelphia - was created in 2005.
I think it's from "It's Always Sunny in Philadelphia"....and I saw him at the Buick Open and "It's Always Sunny in Philadelphia."
The name Philadelphia has five syllables. The syllables of the name are phil-a-del-phi-a.
Kelsey's then Archies Place