paragraph_text: Štefánik's Observatory (, obs. code: 541) is an astronomical observatory on Petřín hill in the center of Prague founded 1928 and named after Slovak astronomer Milan Rastislav Štefánik. Nowadays the observatory specializes above all in popularization of astronomy and related natural sciences.

paragraph_text: Red Lion is an unincorporated community in New Castle County, Delaware, United States. Red Lion is located at the intersection of Delaware Route 7 and Delaware Route 71 northwest of Delaware City and southwest of New Castle.

paragraph_text: The UK Schmidt Telescope (UKST) is a 1.24 metre Schmidt telescope operated by the Australian Astronomical Observatory (formerly the Anglo-Australian Observatory); it is located adjacent to the 3.9 metre Anglo-Australian Telescope at Siding Spring Observatory, Australia. It is very similar to the Samuel Oschin telescope in California. The telescope can detect objects down to magnitude 21 after an hour of exposure on photographic plates.

paragraph_text: The Itapeting Radio Observatory (Portuguese: Rádio Observatório de Itapetinga - ROI) is a radio observatory located in the municipality of Atibaia in the state of São Paulo in Brazil. It is located approximately south of Atibaia and north of São Paulo. ROI was founded in 1970 by Universidade Presbiteriana Mackenzie (UPM). Control of the facility was passed to the National Institute for Space Research (INPE) in 1982. Today it is managed jointly by INPE, UPM, University do Vale do Paraíba (Univap), Universidade de São Paulo (USP), and Universidade Federal de Itajubá (UNIFEI). In addition to the telescopes, the observatory has living quarters for visiting scientists. ROI is located inside a small radio quiet zone.

paragraph_text: Palomar Observatory is an astronomical observatory located in San Diego County, California, United States, southeast of Los Angeles, California, in the Palomar Mountain Range. It is owned and operated by the California Institute of Technology (Caltech) located in Pasadena, California. Research time is granted to Caltech and its research partners, which include the Jet Propulsion Laboratory (JPL) and Cornell University.

paragraph_text: The Monte Mario Observatory (Sede di Monte Mario, literally "Monte Mario Site") is an astronomical observatory and is part of the Rome Observatory (Osservatorio Astronomico di Roma). It is located atop of Monte Mario in Rome, Italy.

paragraph_text: Goldstone Catena (Goldstone Vallis until March 2013) is a catena on Mercury located at 15.8 S, 31.7 W. It is named after Goldstone Observatory. While it superficially resembles a graben, it is a chain of overlapping secondary craters.

paragraph_text: Beijing Astronomical Observatory (BAO) is an observatory located around 150 kilometres northeast of Beijing, China. It was founded in 1958 and is part of the Chinese Academy of Sciences. The observatory comprises 5 observing stations. The principal observing site for optical and infrared is called Xinglong.

paragraph_text: San Pedro Valley Observatory, originally called Vega-Bray Observatory is an astronomical observatory located on a small hill overlooking the San Pedro River Valley, just east of Benson, Arizona (USA). Founded in 1990 by Max Bray, an optician and Dr. Eduardo Vega, a pathologist, it is home to the Hoot-Vega Radio Telescope.

paragraph_text: Wrangle Hill is an unincorporated community in New Castle County, Delaware, United States. Wrangle Hill is located at the intersection of U.S. Route 13, Delaware Route 7, and Delaware Route 72 west of Delaware City. The community was named after a feud between two early families.

paragraph_text: The building was dedicated to Urania, the Muse of Astronomy, and it was named Uraniborg, "The Castle of Urania." It was the first custom-built observatory in modern Europe, though not the last to be built without a telescope as its primary instrument. The cornerstone was laid on August 8, 1576.

paragraph_text: Sherwana Castle, also known as Shirwanah Castle, is located in Kalar, Kurdistan, Iraq. Sherwana Castle is the ancestral home to the Jaff family.

paragraph_text: Viborg and Nyslott County (, ) was a county of the Swedish Empire from 1634 to 1721. The county was named after the castle towns of Viborg () and Nyslott (, literally "New Castle"), today located in the towns of Vyborg in Russia and Savonlinna in Finland.

paragraph_text: Prague Castle General information Architectural style Baroque and Mannerism Location 119 08 Prague 1, Czech Republic Current tenants Miloš Zeman, President of the Czech Republic and the First Lady Construction started 870; 1148 years ago (870) Completed 1929; 89 years ago (1929) Design and construction Architect Matthias of Arras and Peter Parler Website www.hrad.cz

paragraph_text: The McDonald Observatory is an astronomical observatory located near the unincorporated community of Fort Davis in Jeff Davis County, Texas, United States. The facility is located on Mount Locke in the Davis Mountains of West Texas, with additional facilities on Mount Fowlkes, approximately to the northeast. The observatory is part of the University of Texas at Austin. It is an organized research unit of the College of Natural Sciences.

paragraph_text: 651 Antikleia is a main-belt asteroid discovered on October 4, 1907, by August Kopff at the Heidelberg-Königstuhl State Observatory. It is named for Anticlea the mother of Odysseus.

paragraph_text: The Observatory of Turin (, also known as Pino Torinese; obs. code: 022) is an astronomical observatory owned and operated by Italy's National Institute for Astrophysics (, INAF). It is located on the top of a hill in the town of Pino Torinese near Turin, in the north Italian Piedmont region. The observatory was founded in 1759. At Pino Torinese, several asteroid discoveries were made by Italian astronomer Luigi Volta in the late 1920s and early 1930s. The asteroid 2694 Pino Torinese was named after the observatory's location.

paragraph_text: Samair was a charter airline based in Bratislava, Slovakia, operated charter flights out of M. R. Štefánik Airport. It was founded in 2010 inheritor of Central Charter Airlines Slovakia.

paragraph_text: Ritter Observatory is an astronomical observatory owned and operated by the University of Toledo (UT) in Toledo, Ohio (USA). The Ritter Planetarium is located in the same building, and the university also operates Brooks Observatory in an adjacent building. Ritter Observatory features a Ritchey-Chrétien telescope built in 1967 by Warner & Swasey Company of Cleveland, Ohio. It was installed in 1968, and is used primarily for spectroscopy and occasionally for instruction and public viewing events. Research conducted at the observatory focuses on long-term spectroscopic monitoring of stars such as Rigel, Beta Lyrae, and Zeta Tauri.

paragraph_text: Edward Joshua Cooper (May 1798 – 23 April 1863) was an Irish landowner, politician and astronomer from Markree Castle in County Sligo. He sat in the House of Commons of the United Kingdom from 1830 to 1841 and from 1857 to 1859, but is best known for his astronomy, and as the creator of Markree Observatory.

Question: What is the name of the castle in the state where Štefánik's Observatory is located?
Answer: Prague Castle