On June 26, 2012, His Royal Highness Prince Willem-Alexander of Oranje participated in the reopening of the newly restored fortifications of Hellevoetsluis. According to Historiek.net, the restorations of the complex began in 2010 and were funded:
…jointly between the municipality of Hellevoetsluis, the National Service for Cultural Heritage and Europe at a cost of six million Euros.
RVD notes that the construction of the fortress began in the seventeenth century:
… to protect the then naval port Hellevoetsluis. The works were then further developed and expanded. In addition to defensive work, the fortress offered 1,800 to over 4,000 port staff with comfortable housing. The fortress also played a role during the first and second world wars.
Sources: Historiek.net and RVD