Bananas for Scale
Pharos Lighthouse of Alexandria

Photo from Wikimedia Commons

Pharos Lighthouse of Alexandria

One of the Seven Wonders of the Ancient World, guiding ships for 1,500 years/Historical

The Lighthouse of Alexandria (Pharos) was built between 280 and 247 BC on Pharos island in the harbor of Alexandria, Egypt. Ancient sources describe it as approximately 100-130 m tall (estimates vary), making it one of the tallest structures in the ancient world. The lighthouse had three stages: a square base, an octagonal middle section, and a cylindrical top housing the fire and mirror system that could be seen from 47 km away. It stood for roughly 1,500 years before being progressively destroyed by earthquakes between 956 and 1323 AD.

Measurements

Estimated height120 m
6,000Acorn lengths
24Beaver dam lengths

Best scholarly estimate

Base side length30 m
9.1 hundredthsEiffel Towers
30 billionCaffeine molecules

Square base stage

Base height60 m
6,000Tooth lengths
822Lipstick tubes

First (square) stage

Octagonal stage height30 m
100Bread loaves
1.2Clock tower heights

Second (octagonal) stage

Light visibility range47,000 m
5.7 tenthsPanama Canals
1.2 thousandthsEarth circumferences
313,333Hot dogs

Visible from 47 km at sea

Estimated stone mass30 million kg
6 millionHuman heads
13.2 millionBags of flour
484 trillionEyelashes

Limestone and granite blocks

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