The ruins of the palace were almost completely torn down after the war; the outside staircase once leading up to the entrance was salvaged from the debris and moved next to the Orangerie building where it can be seen today. In 2009, it was decided to rebuild the palace. Herrenhausen Palace was reopened on 17 January 2013. Every summer, the Great Garden plays host a large variety of festivals. The "Festival of Small Arts" ("Kleinkunstfestival") takes place over several days and offers a wide range of artistic displays, and the "Small Festival in the Great Garden" ("Kleines Fest im Großen Garten") has become firmly entrenched as a highlight of the "Festival Week Herrenhausen" ("Festwochen Herrenhausen"). Lastly, the garden is the site of an international fireworks competition which evolved from a local attraction. The "State Stage of Hanover" ("Landesbühne Hannover") uses the Garden Theatre of the Great Garden during the summer for both musicals and other theatrical performances. Similarly, the building that houses the garden's orangery is utilized for both art exhibits and performances of classical music; matinee performances are presented in the foyer. The focal point of the garden is the Great Fountain which can, with optimal weather conditions, reach a maximum height of 80 meters. The original fountain was based on ideas of Gottfried Leibniz and was inaugurated in 1719 during the visit of George I. In 1721, it reached a height of some 35 m which made it the highest fountain in European courts. The fountain and its pumping works were renewed in 1860. The Great Garden is also the site of one of the last works of the artist Niki de Saint Phalle. She modified the three-roomed grotto in the northwestern section of the garden, which had served as a store room in the eighteenth century, by adding various items, including crystals, minerals, glass and seashells. Between 2001 and 2003, when the exhibit opened, de Saint Phalle and her coworkers covered the walls and interior with mosaics of molded glass and mirrors. Two rooms branch off from the octagon-shaped central room, and on the front wall of each of them is a statue set within a small recession in the wall. De Saint Phalle's intention for this exhibit was that the visitors could use the grotto as a cool retreat on hot summer days while at the same time being enchanted by the decorations.