Calais Lighthouse is a significant landmark as well as a navigational aid to ships and ferries using the Straits of Dover. There was a beacon at the summit of the watchtower from 1818. King Louis-Philippe in his plans to improve French ports decided the construction of a first-class lighthouse in Calais. This lighthouse started operating in 1848 and was electrified in 1883. After escaping the destruction of the Second World War it was automated in 1987.
The lighthouse is 53m high, its tower is octagonal outside and round inside with walls 1,90m at the base and 1,50m at the summit. The foundations descend 7,40m under the cellars. The staircase has 271 steps leading up to the lantern. The central light of the lighthouse is permanent and the lantern, whose panels shut off the light, turns around the light, giving 4 flashes of 2/10th of a second every 15 seconds.
References:The ancient Argos Theater was built in 320 BC. and is located in Argos, Greece against Larissa Hill. Nearby from this site is Agora, Roman Odeon, and the Baths of Argos. The theater is one of the largest architectural developments in Greece and was renovated in ca 120 AD.
The Hellenistic theater at Argos is cut into the hillside of the Larisa, with 90 steps up a steep incline, forming a narrow rectilinear cavea. Among the largest theaters in Greece, it held about 20,000 spectators and is divided by two landings into three horizontal sections. Staircases further divide the cavea into four cunei, corresponding to the tribes of Argos A high wall was erected to prevent unauthorized access into the theatron and may have helped the acoustics, but it is said the sound quality is still very good today.
Around 120 CE, both theaters were renovated in the Roman style.