The whole of Gunkanjima belonged to the Mitsubishi Company. In this sense it was private land. However, because there were no other private landowners in the vicinity and because all the inhabitants lived on the income from the Mitsubishi corporation in some way, it had the characteristic of public land as far as the inhabitants were concerned. On the island were no roads which would have met the standards of the Road Traffic Act ( except for some imaginary ones on documents to satisfy the legal requirements) nor boundary lines to comply with the Building Standards Act and the Town Planning and Zoning Act. This indicates the fact that Gunkanjima enjoyed a remarkable degree of freedom regarding additions and alterations, because it was possible to ignore constraints which usually apply to high rise such as the right to sunshine, building coverage ratio, the ratio of building volume to lot, height limits, and oblique guidelines projected from adjacent boundaries or the other side of the street. The principle factor which made it possible to juxtapose, adapt and extend building on Gunkanjima in a very free and spontaneous way was that the entire island was in the private possession of a single company. This fact is believed to have played an important part in fostering a sense of unity in the community of residents. 1)It increased the sense of common ownership of the land. 2)It led to a strong determination among inhabitants to utilise what may have been termed the residual space in a positive and independent way in order to improve the quality and utility of the environment. (Fig. 2-9, Ph 2-8 ~ 11).