Explanation:
The median strip is the reserved area that separates opposing lanes of traffic on divided roadways, such as divided highways, dual carriageways, freeways, or motorways. The term also applies to divided roadways other than highways, such as some major streets in urban or suburban areas. The reserved area may simply be paved, but commonly it is adapted to other functions; for example it may accommodate decorative landscaping, trees, a median barrier, or railway or streetcar lines.


http://en.wikipedia.org/wiki/Median_strip


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Note added at 16 mins (2015-05-12 12:11:06 GMT)
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http://ar.wikipedia.org/wiki/جزيرة_وسطى