Lighthouse of Alexandria
Construction
The lighthouse was constructed in the 3rd century BC. After Alexander the Great died, the first Ptolemy (Ptolemy I Soter) announced himself king in 305 BC, and commissioned its construction shortly thereafter. The building was finished during the reign of his son, Ptolemy II Philadelphus, and took twelve years to complete at a total cost of 800 talents of silver. The light was produced by a furnace at the top, and the tower was said to have been built mostly with solid blocks of limestone. Although, since the lighthouse was over 300 feet tall the use of limestone as the main material is doubtful due to the possibility of collapsing under its own weight. Rather, pink granite found nearby is more probable as it is much stronger and can withstand more weight.
Lighthouse of Alexandria-6