Antwerp Citadel (Spanish: Castillo de Amberes, Dutch: Kasteel van Antwerpen) was a pentagonal bastion fort built to defend and dominate the city of Antwerp in the early stages of the Dutch Revolt.

It has been described as "doubtlesse the most matchlesse piece of modern Fortification in the World"[1] and as "one of the most studied urban installations of the sixteenth century".

[2] The citadel was designed by the Italian engineer Francesco Paciotto and built on the orders of the Duke of Alva.

[3] The site became a new neighbourhood of the city, Zuid, in which the most prominent construction was the new building for the Royal Museum of Fine Arts Antwerp.

In the Sint-Joriskerk there is still a brotherhood called Our Lady of the Citadel (Dutch: Onze-Lieve-Vrouw van het Kasteel).