is a name given to gravel
composed of small pieces of rounded stone of
various colors, usually no larger than a large coin. It is named
for the effect of many years of rounding of the edges of the stones
due to a flow of water over it, as often takes place in a river
. River gravel is often used in outdoor settings,
such as a park walkway.
When a hard surface is also desired, river gravel is often set in a
mix. Owing to much higher
cost than either asphalt
pavement, the use of river gravel is generally limited to places
where the appearance and/or its lack of sharp edges (when used
alone) is of primary importance.
American National Park Service's bucolic
Parkway, linking the three points of Virginia's Historic Triangle, has a road surface of
river gravel set in concrete aggregate.
Built between 1930
and 1957, the Colonial Parkway is possibly the longest roadway open
to the public which is surfaced of the material.
River gravel is also occasionally used for landscaping purposes and
placed by landscape architects
in non-traffic areas of high visibility. It may be used with many
plants and shrubs because the rounded surfaces ensure rain and
other water will soak through to reach the roots for necessary