the elevation difference between two adjacent contour lines.
Contour interval
EDITED 1/8/16: A contour interval is a the elevation difference between two adjacent contour lines. Previous person put some ridiculous answer. This one is the correct answer on APEX and does not need improvement.
It would be the difference between the two darker lines, or index lines, and then divide the space in between with your difference.
Most likely you says about contour interval. It's the difference in height between two sequential contour lines. For example, if the contour interval is 50 meters and some contour line corresponds 2000m above sea level, the next contour uphill was at 2050m then 2100m etc. Different maps use different intervals. It depends on map scale and terrain type (for mountain areas intervals are higher than for plains). The contour interval is shown on the map collar (typically near the scale).
The definition of a contour interval is the difference in elevation between two consecutive lines.
The difference in elevation between two contour lines that are side by side is the contour interval. The contour interval is the vertical distance between two adjacent contour lines on a topographic map.
Contour interval.
the elevation difference between two adjacent contour lines.
The difference in elevation between the highest and lowest contour lines on a topographical map is called a contour interval.
The name for the elevation difference between adjacent contour lines is the contour interval.
the space between contour lines
The name for the elevation between two adjacent contour lines is known as the contour interval. It represents the difference in elevation between each contour line on a topographic map.
the contour interval
To find the contour interval on a topographic map, look for the difference in elevation between adjacent contour lines. The contour interval is usually given in the map's legend and represents the vertical distance between each contour line.
Not necessarily but yes, it can be. A contour interval is the difference in elevation between successive contours, while a vertical interval is the distance between any two contours. So yeah, it can be the same sometimes.
Notice the pattern around that contour line. Then determine the interval that the surrounding contour lines are increasing or decreasing by. Ex. 50 100 150 200, the contour interval would then be 50