Palm house is a term sometimes used for large and high heated display greenhouses that specialise in growing palms and other tropical and subtropical plants. In Victorian Britain, several ornate glass and iron palm houses were built in botanical gardens and parks, using cast iron architecture. Especially in English-speaking countries outside the British Isles, these are often called conservatories, in the UK mainly a term for small glass structures attached to houses.
The large example, completed in 1848, in Kew Gardens, London was arguably the first greenhouse to be built on this scale. It was also the first large-scale structural use of wrought iron. The later Temperate House at Kew is in fact even larger. Other British examples are at Liverpool's Sefton Park and Stanley Park. Elsewhere there are the Franklin Park Conservatory in Columbus, Ohio, the Royal Greenhouses of Laeken in Brussels, the Palmenhaus Schönbrunn in Vienna, and many others.