The 
Apennine Mountains stretch 1000 km from the north to the south of 
Italy along its east coast, forming the spine of the country.  They lend their name to the Apennine peninsula which forms the major part of Italy.  The mountains are mostly green and wooded, although the highest peak, Corno Grande (2912 m), is covered by a 
glacier.  The eastern slopes down to the 
Adriatic Sea are steep, while the western slopes form a plain on which most of Italy's historic cities are located.
Historical Significance
In the Italian Campaign of World War II, the Germans used the Apennines as a defensive barrier known to the Allies as the Gothic Line.  The Allies attacked the line unsuccessfully in September 1944.
Another line of defence, the Barbara Line, crossed the southern Apennines.
There is also a range of mountains on the 
Moon called the 
Apennine Mountains, beside the 
Mare Imbrium on which the 
Apollo 15 spacecraft landed.
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