The Royal Botanical Garden was founded by Ferdinand VI in 1755, and was designed by the architects Francisco Sabatini and Juan de Villanueva. Some of its most interesting features include the gates known as the Puerta de Murillo, and the Puerta del Rey, and the Villanueva Pavilion. Its lovely neo-Gothic layout and its location in the centre of the city make it one of the most distinctive botanical gardens in Europe. Since it was first established, one of its main functions has been to investigate, conserve and raise awareness of the world of plants. Its collections include herbaria, the drawings and manuscripts in its archives, and its library. It houses the material collected on the scientific expeditions undertaken in the 18th and 19th centuries to America (Mutis, Ruiz y Pavón, Malaspina, etc.), among others. The flowerbeds feature a display of valuable living plants with over 5,000 different species. It has two greenhouses: the exhibition greenhouse, with three environments (tropical, humid and desert); and the palm hothouse, built in the 19th century. It also has an important collection of Bonsais.