。
She finally arrived at the hotel.
Literal
[topic-は] finally that hotel [at-に] arrived.
やっと ('finally, at last') marks an arrival or completion that came after some difficulty or wait — distinct from ついに ('at last, ultimately') which carries a more dramatic, climactic tone, and 結局 ('in the end, after all') which is more conclusive/summative. に着く ('arrive at') marks the destination with に — に is the standard particle for endpoints of motion verbs.