“Defend both banks of the river Vecht.” That was the mission of the Torenfort aan de Ossenmarkt. This impressive tower fort stands in the fortified city of Weesp. It has a rich history dating back to 1861.
The Torenfort aan de Ossenmarkt was strategically built. It needed to protect the river Vecht. Also it protected the sluices and the Amsterdam-Hilversum railway line. This railway line crossed the river at this point. The fort was part of the New Dutch Water Line. This is a UNESCO World Heritage Site. It also belonged to the Stelling van Amsterdam. The Defence Line of Amsterdam is also a UNESCO World Heritage Site.
Imagine soldiers stationed here in 1914-1918. They were mobilized during World War I. The Torenfort aan de Ossenmarkt was again mobilized in 1940 during World War II. Though it never saw active combat it played a role in the defense.
The Stelling van Amsterdam was a defense line. It stretched 15 to 20 kilometers around Amsterdam’s center. The line was 135 kilometers long. It included 45 forts. Construction took place from 1880 to 1920. The Stelling’s primary function was as a water line. In case of attack large areas around Amsterdam would be flooded. This would stop the enemy’s advance. Amsterdam would serve as a national redoubt. It would be the last stronghold of the Netherlands.
The forts were located where dikes roads or railways crossed the water line. Places with water deep enough for boats were vulnerable. The enemy could advance through these areas. They needed to be under fire.
Around Amsterdam there were posts since 1805. These were the Krayenhoff positions. They consisted of earth and stone forts. Weapon advancements showed that these were not far enough from Amsterdam.
In 1880 the route for a new defense line was established. The design was an improved version of the New Dutch Water Line. The defense line had three parts. These were the inundation areas the military forts and the Amsterdam redoubt.
The area within the fort belt was a national redoubt. In case of an advancing enemy the field army would retreat here. They would hold out with the civilians until help arrived from abroad. The fort needed enough supplies to last six months.
The first object built was Fort bij Abcoude in 1883. It soon became outdated. The arrival of high-explosive shells meant forts needed to be made of concrete.
Many forts were built in polders on peat soil. This had to be replaced with sand for a good foundation. The sand needed to settle for several years before construction.
The forts of the Stelling were built according to a standard model. First the earthworks were constructed. Then sand was brought in. This created a solid base for the buildings. About 1900 piles were driven into the ground for each fort. The walls facing the enemy were 1.5 meters thick. They were made of concrete. The inner walls were 1 meter thick.
Each fort had a garrison of about 300 men. They slept in rooms with 24 to 36 men on straw sacks in bunk beds.
Rainwater was collected for drinking. There were also ways to pump up groundwater. This water contained iron. It had to be treated before use.
The forts also had ventilation systems. These could block airflow during shelling. This prevented pressure from explosions entering the fort.
Today the Torenfort aan de Ossenmarkt houses businesses. A garden center is in the former engineering yard. The wooden artillery shed is an exhibition space. Associations and a music school are also occupants. The fort is not always open. It is partially open to visitors on special occasions. Take a moment to appreciate this historical structure. Its walls hold stories of defense and resilience.