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By the mids, increasingly user-friendly resources such as online mapping in two and three dimensions, integration of GPS with mobile phones and automotive navigation systems appeared.
As of , the future of standardized, centrally printed topographical maps is left somewhat in doubt. Topographic maps have multiple uses in the present day: any type of geographic planning or large-scale architecture; earth sciences and many other geographic disciplines; mining and other earth-based endeavours; and recreational uses such as hiking or, in particular, orienteering, which uses highly detailed maps in its standard requirements.
The various features shown on the map are represented by conventional signs or symbols. For example, colors can be used to indicate a classification of roads. These signs are usually explained in the margin of the map, or on a separately published characteristic sheet.
Topographic maps are also commonly called contour maps or topo maps. In the United States, where the primary national series is organized by a strict 7. Topographic maps conventionally show topography, or land contours, by means of contour lines.
Contour lines are curves that connect contiguous points of the same altitude isohypse. In other words, every point on the marked line of m elevation is m above mean sea level. These maps usually show not only the contours, but also any significant streams or other bodies of water, forest cover, built-up areas or individual buildings depending on scale , and other features and points of interest. Today, topographic maps are prepared using photogrammetric interpretation of aerial photography, LIDAR and other Remote sensing techniques.
Older topographic maps were prepared using traditional surveying instruments. Although virtually the entire terrestrial surface of Earth has been mapped at scale ,,, medium and large-scale mapping has been accomplished intensively in some countries and much less in others. Several commercial vendors supply international topographic map series. It provides topographic maps and data to meet the needs of the sustainable development of the nation. The maps are published at scales , , , and , The Centre for Topographic Information produces topographic maps of Canada at scales of , and , The State Bureau of Surveying and Cartography compiles topographic maps at , and , scales.
It is reported that these maps are accurate and attractively printed in seven colors, and that successive editions show progressive improvement in accuracy. These large-scale maps are the basis for maps at smaller scales. Maps at scales ,, or smaller are exported by Cartographic Publishing House, Beijing while larger-scale maps are restricted as state secrets. China's topographic maps follow the international system of subdivision with , maps spanning 30 minutes longitude by 20 minutes latitude.
The National Land Survey of Finland produces the Topographic Database accuracy and publishes topographic maps of Finland at , and , In addition topographics maps can be viewed by using a free map service MapSite.
In principle, each federal state Bundesland is in charge of producing the official topographic maps. A few areas are also available at , Some private firms sell topographic maps of national parks based on HMGS topography. The Survey of India is responsible for all topographic control, surveys and mapping of India. Standard map scales are ,, ,, , and , Land Information New Zealand is the government agency responsible for providing up-to-date topographic mapping.
Established in , the Survey of Pakistan SOP is based in Rawalpindi with a number of regional offices distributed at urban centers throughout Pakistan. Colonel C.
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