Nagoya is located between Tokyo and Osaka.

Literal

Nagoya [topic-は] Tokyo [and-と] Osaka [possessive-の] between [at-に] exists [polite-ます].

~と~の間 ('between X and Y') is the standard phrase for 'between.' 間 takes に for static location. 名古屋 is Japan's fourth-largest city, in Aichi Prefecture.