Kiyosumi Garden is in Koto-ku, about fifteen minutes east of central Tokyo, and on most days it works as a public park. In the evening, once the gates close, it can be yours. The land was bought in 1878 by Iwasaki Yataro, who founded Mitsubishi and wanted somewhere to entertain his staff and his business guests. The garden was finished after he died. Water was drawn in from the Sumida River, and the family shipped in stones from all over Japan, enough of them and good enough that people began calling it the Garden of Famous Stones. Tokyo has since designated it a Place of Scenic Beauty. Dinner is in the Taisho Kinenkan, a hall on the edge of the pond with windows down one side. It seats about 100 for a course meal, or 130 for a standing reception. Before you sit down a guide can walk you round the garden, and drinks can be served on lawns that are normally roped off. Two things to look for on that walk. The stepping-stone path runs right at the surface of the water, close enough that the birds do not bother moving. And the Ryotei, a small teahouse the Iwasakis built in 1909 for a visiting British field marshal, leans out over the pond. The garden reads differently in each season. Cherry in early April, maples in late November.