Uranienborg (Uraniborg) was a Danish astronomical observatory operated by Tycho Brahe. It was built circa 1576-1580. Shortly after its construction the observatory was expanded with an underground facility, Stjerneborg, on an adjacent site. The building was dedicated to Urania, the Muse of Astronomy and named Uranienborg, "The Castle of Urania." It was the first custom-built observatory, and the last to be built without a telescope as its primary instrument.
The main building of Uraniborg was square, about 15 meters on a side, and built mostly of red brick. Two semi-circular towers, one each on the north and south sides of the main building, giving the building a somewhat rectangular shape overall. The observatory had a large mural quadrant affixed to a north-south wall, used to measure the altitude of stars as they passed the meridian. This, along with many other instruments of the observatory, was depicted and described in detail in Brahe's 1598 book Astronomiae instauratae mechanica.
A large wall, 75 meters on a side and 5.5 meters high was planned to surround Uraniborg, but never built, instead a high earth mound was constructed and lasted until today being the only remnant of the observatory still in place. Uraniborg was located in the very middle, with an extensive set of intricate gardens between the mound walls and the building. In addition to being decorative, the gardens also supplied herbs for the Tycho's medicinal chemistry experiments. The gardens are currently being re-created, using seeds found on-site or identified in Tycho's writings.
Uraniborg was an extremely expensive project. It is estimated that it cost about 1% of the entire state budget during construction.
Shortly after construction it became clear that the tower-mounted instruments were too easily moved by wind, and Tycho set about constructing a more suitable observation site. The result was near Stjerneborg a smaller site built entirely at ground level and dedicated purely to observations. The basic layout was similar to Uraniborg, with a wall of similar shape surrounding the site, although the enclosed area was much smaller. The instruments were all placed underground, covered by opening shutters or a rotating dome in buildings built over the instrument pits.
Upon losing financial support from the new king, Christian IV of Denmark, Tycho abandoned Hven in 1597 and both Uraniborg and Stjerneborg were destroyed shortly after Tycho's death. Stjerneborg was the subject of archaeological excavations during the 1950s, resulting in the restoration of the observatory. Stjerneborg now houses a multimedia show. The Round Tower in Copenhagen was inaugurated in 1642 as a replacement. The grounds are currently being restored.References:
The Mosque–Cathedral of Córdoba, also known as the Great Mosque of Córdoba and the Mezquita is regarded as one of the most accomplished monuments of Moorish architecture.
According to a traditional account, a small Visigoth church, the Catholic Basilica of Saint Vincent of Lérins, originally stood on the site. In 784 Abd al-Rahman I ordered construction of the Great Mosque, which was considerably expanded by later Muslim rulers. The mosque underwent numerous subsequent changes: Abd al-Rahman II ordered a new minaret, while in 961 Al-Hakam II enlarged the building and enriched the Mihrab. The last of such reforms was carried out by Almanzor in 987. It was connected to the Caliph"s palace by a raised walkway, mosques within the palaces being the tradition for previous Islamic rulers – as well as Christian Kings who built their palaces adjacent to churches. The Mezquita reached its current dimensions in 987 with the completion of the outer naves and courtyard.
In 1236, Córdoba was conquered by King Ferdinand III of Castile, and the centre of the mosque was converted into a Catholic cathedral. Alfonso X oversaw the construction of the Villaviciosa Chapel and the Royal Chapel within the mosque. The kings who followed added further Christian features, such as King Henry II rebuilding the chapel in the 14th century. The minaret of the mosque was also converted to the bell tower of the cathedral. It was adorned with Santiago de Compostela"s captured cathedral bells. Following a windstorm in 1589, the former minaret was further reinforced by encasing it within a new structure.
The most significant alteration was the building of a Renaissance cathedral nave in the middle of the expansive structure. The insertion was constructed by permission of Charles V, king of Castile and Aragon. Artisans and architects continued to add to the existing structure until the late 18th century.
The building"s floor plan is seen to be parallel to some of the earliest mosques built from the very beginning of Islam. It had a rectangular prayer hall with aisles arranged perpendicular to the qibla, the direction towards which Muslims pray. The prayer hall was large and flat, with timber ceilings held up by arches of horseshoe-like appearance.
In planning the mosque, the architects incorporated a number of Roman columns with choice capitals. Some of the columns were already in the Gothic structure; others were sent from various regions of Iberia as presents from the governors of provinces. Ivory, jasper, porphyry, gold, silver, copper, and brass were used in the decorations. Marvellous mosaics and azulejos were designed. Later, the immense temple embodied all the styles of Morisco architecture into one composition.
The building is most notable for its arcaded hypostyle hall, with 856 columns of jasper, onyx, marble, granite and porphyry. These were made from pieces of the Roman temple that had occupied the site previously, as well as other Roman buildings, such as the Mérida amphitheatre. The double arches were an innovation, permitting higher ceilings than would otherwise be possible with relatively low columns. The double arches consist of a lower horseshoe arch and an upper semi-circular arch.