It is located in the present-day town of Nagawa, in the Chiisagata District of Nagano Prefecture, Japan.
Much of the original town was destroyed by a flood in 1631, and relocated a slight distance to higher ground.
As the town developed, its row houses eventually spread to side streets, giving it the rare shape of a key.
Per an 1843 guidebook issued by the Inspector of Highways (道中奉行, Dōchu-būgyō), there were over 187 inns in which travelers could rest, including one honjin, one waki-honjin, and 43 hatago, with a total resident population of 721 people.
Many of the buildings of Nagakubo-shuku have been preserved, and the area is a tourist attraction within the town of Nagawa.