In this study I examined the features of machiya (traditional townhouses) in the Takehara Preservation District for Groups of Historic Buildings. An investigation was made of such details as the overall design, the age of the building, scales, the form of the earthen floor, the odo (large main door), the butyo, and the second-floor walls. This study also considers the reason for the coexistence of such features as the tsumairi (traditional architectural style in which the main entrance is on one or both of the gabled sides) and hirairi (traditional architectural style in which the building has its main entrance on the side running parallel to the roof ridge) in the machiya of the Edo period (1603-1867). The results lead to the supposition that this circumstance arose through legal restrictions on the length of beams imposed by the shogunate during Edo times.