The word 'runway' is a noun; a singular, common, compound noun.
"Park Avenue" is a proper noun, because it is a place. Proper nouns like this should always be capitalized.
proper
Highway Doorway and Runway
b or right a or left
Common
common and proper
common
common
It is a proper noun, because it is the name of a specific thing.
it's a common noun. a proper noun would be Spider-Man.
Proper