The structure is a replica of a famous gateway in Japan. It was made for an exhibition in London in 1910, and when this finished, it was presented to Kew for display in the gardens. The building is a softwood timber framed construction, probably Cedar, with elaborate carvings and applied copper repousse details.

The structure comprises six substantial posts with rails at mid height on the North and South sides. Gablets present to the North and South and contain iconographic carving set above a timber sill. The roof is clad with small, welted copper shingles with very heavy metallic glazed terracotta ridge tiles.

Except for the slight change of roof covering details, the original was thatch, the terracotta ridge and finials appear exactly as they did in 1910, as do the white painted corbels and all of the carpentry.

Martin Ashley Architects were asked to carry out a survey in March 2021 by RBG Kew to assess the condition of the structure and finishes.