The night grew late and I was tired, so I stayed at an inn.
Literal
Night [subj-が] deepen-[and-て] was-tired-[because-ので] I [topic-は] inn [at-に] stayed-overnight.
Two causes joined by the te-form 更けて ('night deepening (and)') + negative-turned-copular past 疲れていた ('being tired') + ~ので. 宿屋 ('inn, traditional lodging') is the classical word for an inn; the modern 宿 is a clipped version. A narrative typical of travel/folk stories.