ABOUT: GTR-DVD-1088 - The tall minarets of the Sultan Ahmet Mosque, known also as the Blue Mosque, tower proudly into the heavens and dominate the skyline of Istanbul, the Turkish capital on the Bosporus. At the beginning of the 17th century the young and ambitious sultan, Ahmet The First, decided that an additional building should replace the Hagia Sophia as the city's main mosque. With its graduated cupolas, the building was designed to be as impressive as possible, thus a spacious courtyard was also included. Elegant columned halls surround a square at the centre of which there is an hexagonal fountain where the faithful once cleansed themselves prior to prayer. Today, the faithful wash themselves along the external sidewalls of the courtyard. In the eastern section is the Mederse, the mosque's School of the Koran. Four massive five metre thick pillars known as 'Elephants' Feet' support the incredible weight of the Blue Mosque's massive central cupola. It derived its popular alias of the Blue Mosque due to its internal décor that consists of twenty-one thousand precious blue coloured Fayence wall tiles from Iznik. The Topkapi Palace, which over the years was greatly extended by various sultans, is also located in the historic centre of Istanbul and until 1853 it was the royal residence of the Osmanic royal family. Along the picturesque shoreline of the Bosporus are numerous ancient mosques, palaces and villas and one of the longest and most impressive suspension bridges in the world connects this fascinating European city and its twelve million inhabitants to Asia. Global Treasures - History's Most Protected Monuments - Heritage is our legacy from the past, what we live today, and what we pass on to future generations. our cultural and natural heritage are both irreplaceable sources of life and inspiration. Places as unique and diverse as the wilds of East Africa's Serengeti, the Pyramids of Egypt, the Great Barrier Reef in Australia and the Baroque cathedrals of Latin America make up our world's heritage. Join us as we explore one of these protected monuments.