This is the 8023rd most frequent Russian word.
красногородского
"Красногородского" is the genitive or adjective form related to "Красногородск," a town in Russia, meaning "of Krasnogorodsk" or "Krasnogorodsk's."
Here, 'красногородского' is used in the genitive case to indicate possession or relation ('of the Krasnogorodsky district').
Он отправился в красногородского района для изучения местной культуры.
He traveled to the Krasnogorodsky district to study local culture.
In this sentence, 'красногородского' is in the genitive case used as an attributive modifier ('of Krasnogorodsky museum').
В одном из красногородского музеев проходят интересные выставки.
Interesting exhibitions take place in one of the Krasnogorodsky museums.
Here, 'красногородского' is used as an adjective in the genitive case modifying 'forum' in terms of ownership or affiliation.