The site's history extends back over two thousand years and includes Iberian, Roman and medieval remains.

In 1811, during the Napoleonic Wars, the French laid siege to the castle, and were ultimately successful in taking it, after which the defences were repaired.

[10] The visible ruins are essentially those of the Muslim citadel, with later modifications under Christian rule, and finally by French engineers during the Peninsular War.

[11] The curtain wall mostly dates to the Islamic period; it descended from the castle to connect to a series of fortifications laid out around the town below.

It underwent substantial modifications from the Christian period through to the Peninsular War, with Gothic and Renaissance reworking of Muslim fortifications.

The hilltop was levelled, and retaining walls reinforced by buttresses supported the artificial platform that served as a foundation for the forum.

The Carthaginian general Hannibal sacked the Iberian settlement in 219 BC, an action that led to the outbreak of the Second Punic War.

[11] 8th century Arab records from the reign of Abd al-Rahman I (ruled 755–788 AD) indicate that Sagunto fell within the jurisdiction of Tortosa at that time, rather than that of Valencia.

[16] Muslim historian Ibn Hayyan recorded that the castle was taken by force in 929–930, and mentions it again, under its Arab name, as submitting to the sultan Abd-ar-Rahman III in 933 AD.

It was seized and occupied by El Cid from 1098 to 1102,[18] and was definitively removed from Muslim rule by Christian king Jaume I in 1238,[19] who incorporated it into the Kingdom of Valencia.

[11] During the Spanish War of Succession, in the early 18th century, the castle was surrendered to the Archduke of Austria, but soon afterwards it passed under the control of King Philip V of Spain.

[18] In 1811, during the Peninsular War, Brigadier Andriani defended the castle against French troops commanded by General Suchet,[22] who laid siege to the fortress on 23 September of that year.

[11] In 1932, M. González Simancas excavated the general area of the Roman remains in the Plaza de Armas,[25] but left few records of his investigations.