The Great Barrier Reef is the world's largest coral reef systemcomposed of over 2,900 individual reefs and 900 islands stretching for over 2,600 kilometres (1,600 mi) over an area of approximately 344,400 square kilometres (133,000 sq mi).The reef is located in the Coral Sea, off the coast of Queensland, Australia.
The Great Barrier Reef can be seen from outer space and is the world's biggest single structure made by living organisms. This reef structure is composed of and built by billions of tiny organisms, known as coral polyps.It supports a wide diversity of life and was selected as a World Heritage Site in 1981. CNN labeled it one of the seven natural wonders of the world.The Queensland National Trust named it a state icon of Queensland.
A large part of the reef is protected by the Great Barrier Reef Marine Park, which helps to limit the impact of human use, such as fishing and tourism. Other environmental pressures on the reef and its ecosystem include runoff, climate change accompanied by mass coral bleaching, and cyclic population outbreaks of the crown-of-thorns starfish. According to a study published on 1 October 2012 by the Proceedings of the National Academy of Sciences, the reef has lost more than half its coral cover since 1985. Maldives
Maldives consists of 1,192 coral islands grouped in a double chain of 26 atolls, along the north-south direction, spread over roughly 90,000 square kilometres (35,000 sq mi), making this one of the world's most dispersed countries. It lies between latitudes 1°S and 8°N, and longitudes 72° and 74°E. The atolls are composed of live coral reefs and sand bars, situated atop a submarine ridge 960 kilometres (600 mi) long that rises abruptly from the depths of the Indian Ocean and runs north to south. Only near the southern end of this natural coral barricade do two open passages permit safe ship navigation from one side of the Indian Ocean to the other through the territorial waters of Maldives. For administrative purposes the Maldivian government organised these atolls into twenty one administrative divisions. The largest island of Maldives is Gan, which belongs to Laamu Atoll or Hahdhummathi Maldives. In Addu Atoll the westernmost islands are connected by roads over the reef (collectively called Link Road) and the total length of the road is 14 km (9 mi).
Maldives is the lowest country in the world, with a maximum natural ground level of only 2.4 metres (7 ft 10 in), with the average being only 1.5 metres (4 ft 11 in) above sea level, although in areas where construction exists, this has been increased to several metres. However, more than 80 per cent of the country's land is composed of coral islands that rise less than one metre above sea level.
The reef is composed of coral debris and living coral. This acts as a natural barrier against the sea, forming lagoons. Other islands, set at a distance and parallel to the reef, have their own protective fringe of reef. An opening in the surrounding coral barrier allows access to the calmer lagoon waters. The barrier reefs of the islands protect them from the storms and high waves of the Indian Ocean. Venice
Venezia is a city of small islands, enhanced during the Middle Ages by the dredging of soils to raise the marshy ground above the tides. The resulting canals encouraged a nautical culture to flourish, which proved central to the economy of the city. Today those canals still provide the means for transport of goods and people within the city.
The maze of canals threaded through the city requires the use of more than 400 bridges to permit the flow of foot traffic. In 2011 the city opened Ponte della Costituzione, the fourth bridge across the Grand Canal, connecting the Piazzale Roma bus terminal area with the Stazione Ferroviaria (train station), the others being the original Ponte di Rialto, the Ponte dell'Accademia, and the Ponte degli Scalzi.
Azienda Consorzio Trasporti Veneziano (ACTV) is the name of the public transport system in Venice. It combines land transportation, with buses, and canal travel, with water buses (vaporetti). In total, there are 25 routes that connect the city.
The main public transportation means are motorised waterbuses (vaporetti), which ply regular routes along the Grand Canal and between the city's islands. The only gondole still in common use by Venetians are the traghetti, foot passenger ferries crossing the Grand Canal at certain points without bridges.
The Venice People Mover (managed by ASM) is a cable operated public transit system connecting Tronchetto island with Piazzale Roma. Water taxis are also active.
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