The Hondsbossche Sluis is the historical lock in the center of Zaandam, The Netherlands. After some five ages the lock still functions and is operated by a group of fifty volunteers.
The lock is currently closed for the winter. In 2025, 8,122 vessels passed through the lock. This is roughly the same as last year, despite the high number of vessels passed during Sail2025: 1,542. On the opening day of Sail, August 20, 2025, an all-time record number of vessels passed: 379. During the 2025 sailing season, the lock was closed for only 41 half-days because the pumping station had to discharge water from North Holland. But there were also other reasons this year that the lock could not open. Due to damage to the lock gate, we were closed from August 9 to 13, 2025 (10 half-days). And on July 1 and 2, it was so hot that locking the lock was irresponsible for the lock keepers. All in all, we were open for passage on 83% of the 330 available half-days (in 2024: 66%). The 2025 annual calendar can be found here. Het overzicht van het aantal doorvaarten 2015-2025 is here .
Stories about the lock
Reconstruction of the Harbour office, August 2025: “Exactly two years ago today, the regional Dagblad Zaanstreek opened with the headline: ‘Construction of port office can start, the question is when’.
The Zaandamse Overtoom, March 2024: “Between 1609 and 1718, there was a wooden ramp to the west of the Hondsbossche Sluis to drag ships over the dam from the Binnenzaan to the Voorzaan: the Zaandam 'overtoom'….”
Cottages and 'smuigers', July 2023: “There are two houses on the south side of the lock. They were built in 1724….”
The bridge was open…. , April 2023: “If you thought that getting stuck in traffic is a modern annoyance…”
A lock keepers family, February 2023: "In 1935, Cornelis Swartsenburg and his young family lived at Hoogedam 11, in the cramped, damp house on the southeast side of the lock...."
Near miss, December 2022: "This photo from 1955 shows that there was not only sailing and waiting in the lock...."
Lock keeper Groot, December 2022: “The photo below from 1930 clearly shows that recording memories is full of pitfalls...”
The latest news
Sail 2025
From August 20th to 24th, 2025, Sail returned to Amsterdam's IJ waterway after a 10-year absence. The lock operated almost continuously between 8:30 AM and 10:00 PM. It was sunny, the atmosphere was excellent, the spectators were numerous, and the lock keepers were enthusiastic. Over the four days, 1,542 boats were locked through. Fellow lock keeper Madelon created a wonderful cinematic impression.
Damage on the lock door
On 17 or 18 June 2025, a boat from the inside collided with the southern lock gate at full speed. The impact must have been so hard that the connecting bracket to the turning beam was completely bent back. The lock could no longer be operated properly.
After one phone call, Van Kaaik employees were immediately on site to forge the bracket back into its curved shape with a blowtorch and a sledgehammer. Great work!
The perpetrator is on the run……
On August 8, 2025, it happened again. A pleasure craft on a trial run rammed the southern lock gate. The gate was completely dislocated, and one of the turnstiles was broken. With Sail 2025 approaching, the municipality acted quickly. The lock was back in operation on August 14!
New signs about the history of the lock
On Monday 14 April 2025, new signs were placed on the bridge railings telling the history of the lock. In two languages, with a slightly larger font and with somewhat shorter texts than on the old signs. You can find them here.
Passages
In 2024, 7990 ships passed through the lock. Although that number is one of the lowest scores in the past 10 operating seasons, it was not too bad. In 2024, the lock was closed for 108 half days because the pumping station had to discharge water from North Holland. That is almost 1/3 of the number of half days that we wanted to be open. The busiest day of the year was Sunday 11 August 2024: 292 passages. At the end of the season, it was again a wet affair: on those 18 half days, we let 13 boats through.
This is the overview of the number passages 2025-2024
Registrations
New volunteers are very welcome! If you would like to be a lock keeper, please contact the board of the Volunteer Lock Keepers Hondsbosschesluis Zaandam Foundation by using the contact form at the bottom of this page.
De Orkaan
De Hurricane is the unparalleled newspaper about the Zaanstreek. Half of the content is filled by people who are interested in the history and development of the region. The editorial staff fills the other half of the website. De Hurricane started in 1986 as a paper newspaper but went under after just five issues. In 2014 a new start was made (just like our lock) and since then the Zaanse news has been omnipresent on social media: the Web, Facebook, Instagram, X, LinkedIn and Youtube.
Over the past year, the Hurricane has regularly posted messages that tell something, indirectly but sometimes directly, about the Hondsbossche Sluis. Lock keeper Ger keeps an eye on the Hurricane and has made the following selection.
- Groote sluis met accijnshuisjes en Hotel Suisse
- Achterzaan vanaf de Hondsbossche Sluis
- De ‘Oude Sluis’ in Zaandam
Read that magazine!
Repairs
When the lock is closed in winter, repairs are carried out on the lock walls. The masonry joints were in poor condition in some places, or even completely gone. A specialized company carried out repairs, partially underwater.
Contact
You can send a message to the board of the Volunteer Foundation Hondsbosschesluis Zaandam using the form below. For example, to register as a new volunteer or to give tips, ask questions, share an opinion or send a compliment.
EN 
NL 