Москва, Калуга, Пенза, Кострома
All these toponyms end on -a and, as far as I know, they are all feminine.
However, I know that in Russian some nouns ending on -a can be masculine:
ябеда, неряха, голова, воевода, непоседа, жадина
including some forms of proper nouns:
Петруха, Серёжа, Саша, Вова, Миша
Аre there any masculine toponyms in Russian ending on -a?