The legendary temple of Hercules Gaditanus, who was known as Melqart in Phoenician times, was a key pilgrimage site in ancient times. According to classical records, the temple witnessed the passage of historical figures such as Julius Caesar and the Carthaginian conqueror Hannibal, and dated at least as far back as the ninth century BC.
Measuring 300 by 150 meters – like the island on which it stood – the rectangular structure lies between five and three meters underwater and seems to fit with descriptions in the classics that describe both the location of the temple and its definition as a great Phoenician monument.
The new hypothesis of the location of the temple fits with various findings and proposals made throughout the 20th century, but also differs from others, the last of which was The location of the sanctuary of Melqart in Gadir: contribution of the PNOA-LiDAR data, by Antonio Monterroso-Checa, professor in the Archaeology department at Córdoba University.
Source: english.elpais.com/culture