。
She visited the house several times.
Literal
She [topic-は] that house [to-に] several-times feet [object-を] carried.
足を運ぶ — literally 'to carry one's feet' — is a fixed idiomatic phrase for paying a visit, going somewhere in person. The connotation is of effort: not just dropping by, but going out of one's way to be there. 何回か ('a few times, several times') leaves the count vague; 何 with か here means 'an unspecified number'. Compare 何回 ('how many times?', a question) without か — the か turns the wh-word into an indefinite. に marks the destination of the visiting.