The Temperate House conservatory at the Kew Gardens in Richmond upon Thames has just re-opened after some years of restoration by Donald Insall Associates. The architecture studio, specialized in preserving historical buildings, took this project in 2012. The Temperate House is the hugest Victorian glasshouse in the world, a masterpiece of the 19e century by Decimus Burton in 1860. It hosts more than 10,000 rare and endangered plants. In 2003, UNESCO included the building among its protected worldwide cultural places. In 2012 English Heritage proposed placing the Temperate House on the Buildings at Risk register. This historical architectural legacy has been finally magnificently appointed and it is open again to visitors.