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A Topographical Map is a
drawing that represents an area of the Earth's
surface with distinctive land-surface
characteristics represented as contour lines and a
set of graphic symbols representing other features
found on the Earth. Topographical map contours
are imaginary lines that join points of equal
elevation on the surface of the land, above or below
a reference surface, such as "mean sea level".
Contours make it possible to measure the height of
mountains, depths of the ocean bottom, and steepness
of slopes from a topographical map.
A topographic map contains more
than contours. The Topographical map includes
symbols that represent such features as streets,
buildings, streams, and vegetation. These
symbols are constantly refined to better relate to
the features they represent, improve the appearance
or readability of the map, or reduce production
cost. Each country defines a set of standard
symbols to be used on all of their officially
printed topographical maps.
Consequently, within the same
series, maps may have slightly different symbols for
the same feature. Examples of symbols that
have changed include built-up areas, roads,
intermittent drainage, and some lettering styles.
On one type of large-scale topographic map, called
provisional, some symbols and lettering are hand
drawn.
Always seek out the countries
official topographical map guide, which should
include the most complete index and definitions to
the symbols used. Also, Always seek out
the most recent published maps available for an area
that will be navigated!
Reading
Topographical Maps
Interpreting the colored lines,
areas, and other symbols is the first step in using
topographic maps. Features are shown as
points, lines, or areas, depending on their size and
extent. For example, individual houses
may be shown as small black squares. For
larger buildings, the actual shapes are mapped. In
densely built-up areas, most individual buildings
are omitted and an area tint is shown.
On some maps, post offices, churches, city halls,
and other landmark buildings are shown within the
tinted area.
Consequently, within the same
series, maps may have slightly different symbols for
the same feature. Examples of symbols
that have changed include built-up areas, roads,
intermittent drainage, and some lettering styles. On
one type of large-scale topographic map, called
provisional, some symbols and lettering are hand
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