Look for the Former Imperial Rest House. It was built in 1896 as a resting place for the Emperor and members of the imperial family when they came to admire the garden's greenhouse. It was enlarged to its present size in 1924 and used as a clubhouse. Designed by the Imperial Household Ministry's architecture office, it is based on the American Stick Style and has been an Important Cultural Property since 2001. Nearby is the Former Goryotei, a pavilion by the water used as a cool summer retreat. It was a gift from Taiwan to mark the wedding of the future Showa Emperor. You can also find the excavated remains of an early greenhouse, built between 1893 and 1914 and uncovered in 2010. Its cut stone and brick show how greenhouses were built in that era. The modern greenhouse stands near the Okido Gate and covers 2,750 square meters. It shows tropical plants from mountain regions and lowlands, and subtropical plants from Okinawa and the Ogasawara Islands. The garden grows about 2,700 species, many of them tropical or subtropical, and it also works to conserve endangered plants. Out on the grass, the English landscape garden is the largest of the three, a wide lawn ringed by tall trees. The garden's symbol tree is the tulip tree, rising over 30 meters, with soft yellow-green flowers around May. If you want the whole story indoors, a permanent exhibition facility tells four centuries of the garden's history with immersive projections and displays on the greenhouse, the cherry and chrysanthemum blossoms, and the imperial garden era.