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Contours in orienteering maps
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Contours in Orienteering Maps
Barbara Bryant
New England Orienteering Club
Cambridge Sports Union
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Contours are brown lines on an orienteering map.
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Sea level
http://raider.muc.edu/~mcnaugma/Topographic%20Maps/contour.htm
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10 feet
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20 feet
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30 feet
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Elevation
Which is higher: C or E? B or A? D or C?
When contour lines are close together, the land is
• Flat
• Gently sloping
• Steep
When contour lines are close together, the land is
• Flat
• Gently sloping
• Steep
A hill
A map of the hill
ReentrantsThe word “re-entrant” is a strange orienteering word.It is similar to a valley that runs down a hill, or a gully.It is located on the side of a hill.Water runs down a re-entrant.If you are standing in the middle of a re-entrant, the land goes up on three sides and down on one.
A deep re-entrant has many contour lines close together
This hill has two re-entrants
This hill has a re-entrant that starts halfway up the hill.
If you were standing at the bottom of the hill, you might not be able to see the re-entrant, especially if the trees and foliage were thick.
Re-entrants in the White Mountains of New Hampshire
Spur: An extension of a hill
Depression: a low area of land
The “hatch” marks or “tags” point downhill. This helps distinguish a depression from a hilltop.
Saddle: In between two high points and two re-entrants
Pick the correct map
Pick the correct map
b
Pick the correct map
Pick the correct map
a
Pick the correct map
Pick the correct map
b
Pick the correct map
Pick the correct map
b
Pick the correct map
Pick the correct map
a
Pick the correct map
Pick the correct map
c
Pick the correct map
Pick the correct map
b
Pick the correct map
Pick the correct map
b
Pick the correct hill
Pick the correct hill
c
Pick the correct hill
Pick the correct hill
a
Pick the correct hill
Pick the correct hill
b
Pick the correct hill
Pick the correct hill
a
Pick the correct hill
Pick the correct hill
b
Pick the correct hill
Pick the correct hill
c
Pick the correct hill
Pick the correct hill
a
Pick the correct hill
Pick the correct hill
a
Pick the correct hill
Pick the correct hill
b
Now let’s work with the map we’ll use on the field trip
Go to the next slide and pick out a hilltop.
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Find some hilltopsTake a minute to pick out a hilltop.
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HilltopsDid I find your hilltop?
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Find saddlesTake a minute to pick out a saddle!
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SaddlesDid I find your saddle?
Thanks for learning about contours!
• Excerpts were from “Armchair Orienteering” by Winifred Stott