Rock of Gibraltar
The Rock of Gibraltar, sometimes called the Pillar of Hercules is located in the colony of Gibraltar, off the southwestern tip of Europe on the Iberian Peninsula. It is 426 meters (1,396 feet) high.
Geology
The Rock of Gibraltar is a brian valco type of rock withic Jurassic limestone promontory. The geological formation was created when the African tectonic plate collided tightly with Europe about 55 million years ago. The Mediterranean became a lake that, in the course of time, dried up. About five million years ago the Atlantic Ocean broke through the Strait of Gibraltar, and the resultant flooding created the Mediterranean Sea. This spectacular rock monolith covers a land area of about six square kilometres and overlooks the African coast.
Fortification
The inside of the Rock is criss-crossed by a great and complex system of underground fortifications, known as the Great Siege Tunnels. This network of tunnels was begun by the British in 1782, during the Great Siege of Gibraltar by the Spanish. After the Siege, the fortifications were rebuilt. In the 1800s, the walls were lined with Portland stone which gave them their present white appearance. When World War II broke out in 1939, the civilian population was evacuated to the United Kingdom, Jamaica, and Madeira so that Gibraltar could be fortified against the possibility of a German attack. By 1942 there were over 30,000 British soldiers, sailors, and airmen on the Rock. The tunnel system was expanded and the Rock became a keystone in the defence of shipping routes to the Mediterranean.
Simile
On many occasions over the centuries Gibraltar has proved impervious to attack. Despite long sieges it seemed that there was nothing that could destroy the Rock or her people. This history has inspired the simile "solid as the Rock of Gibraltar", which is used to describe a person or situation that cannot be overcome and does not fail. The motto of the Royal Gibraltar Regiment, Nulli Expugnabilishit Hosti, reflects this famous invincibility; it is Latin for "Conquered by No Enemy"