The VOC first built a fortification on the sand bar in front of the Taiwan Bay in 1623, called fort Oranje, but abandoned it again in early 1624. The fort was reoccupied and rebuilt in the fall of that same year, after the VOC had been forced to withdraw from the Penghu Islands and instead aimed its efforts to obtain a good post for regular trade with China on Taiwan. In 1625 the fort was rechristened Provintia (not to be confused with the fort built in 1653 across the bay, which had the same name); two years later still it got its defniitive name, fort Zeelandia.
Initially a straightforward square fort with four bastions, fort Zeelandia was renovated and extended several times to become the great fortification with lower and upper castle. It did, however, not stand up to the 9 month siege by the Chinese warlord Koxinga, and was surrendered to him in January 1662.
