This is the 8130th most frequent Russian word.
ленинграду
"Leningradu" is the dative case of "Ленинград" (Leningrad), the former name of St. Petersburg, meaning "to Leningrad" or "for Leningrad."
Dative case used to express direction towards a place.
Я однажды был в Ленинграду.
I once visited Leningrad.
Dative case used to indicate the indirect object of the action.
Мы посвятили песню Ленинграду.
We dedicated a song to Leningrad.
Dative case mistakenly used, as it should be prepositional case 'о Ленинграде'.