HNLMS Tonijn

The HNLMS Tonijn is a Potvis-class submarine with three separate cylindrical pressure hulls arranged in a distinctive triangular pattern. Visitors can explore the control room, torpedo compartment, crew quarters, and engine sections, all preserved in their original working condition.

The vessel operated from 1966 until 1991, conducting surveillance missions against Soviet ships during the Cold War. It participated in numerous NATO exercises across Atlantic and European waters throughout its service years.

Former crew members serve as guides, sharing stories about how sailors lived and worked in these tight spaces beneath the waves. Their accounts reveal the daily rhythms and bonds that developed among men serving in such confined quarters.

Visitors should expect narrow passageways and low ceilings throughout, as submarine design prioritizes compact spaces. Comfortable shoes are recommended, and time should be set aside to properly explore the various compartments and sections.

In 1979, a critical incident occurred onboard when fires broke out in both engine rooms, causing complete battery failure. The vessel had to be emergency towed to Gibraltar, highlighting the vulnerabilities of early Cold War submarine designs.

Location: Den Helder

GPS coordinates: 52.96377,4.77126

Latest update: December 11, 2025 11:03