Phipps Conservatory and Botanical Gardens is one of America's most historic public gardens, full of exotic plant species since 1893. Its elaborate 15-acre (six-hectare) layout features mostly floral exhibits, as well as steel and glasswork Victorian greenhouse architecture. The conservatory was founded in the late 19th century by local steel magnate Henry Phipps and later given to the city of Pittsburgh. Today, it is a National Historic Landmark, as well as one of the greenest buildings in the country with a LEED-certified visitor center and production greenhouse.