Dutch Water Line
On 1573 at the beginning of the eighty
years war against Spain, the Dutch used for the first time
water by flooding the land to break the siege of
Spanish troops on the town Alkmaar.
Because much of Holland is below sea
level, this tactic could be used and was applied frequently
throughout this war.
In 1574, flooding the land prevented Spanish troops seiging Gorinchem
which town took the side of the Prince of Orange in 1572.
Have patience, to see great pictures !!
Last revised on 16-feb-2013
Also in 1574, Spanish troops besieged the town (upper right) Leiden.
Then the Dutch flooded the land around the town.
As you can see, the Spanish made strongholds with little dikes like walls around them, also
controlling the river to the town.
However the water level on the flooded land became high enough to allow a fleet of Dutch
freedom fighters, named "Geuzen", to row their boats around the Spanish strongholds and
free the town.
In 1629 Prince Frederik Henderik starts executing a plan from 1589
made by Prince Maurits, for a defense line, making use of a string of pieces of land, that can
be flooded in front of the defenders.
The line runs at first from the
inland sea "Zuiderzee" in south direction to the first big river and is later on
extended to the river "Merwede" at Gorinchem.
Holland was the rich part and economical center of the
Netherlands housing also the government.
The defense line was made in the most easterly part of Holland
that could be flooded easily.
Further to the east there was higher ground, that could not
be flooded very easily. Also this part of the land had mostly
agricultural activity and was less important to defend.
This picture shows the first line and the invading forces at
several occasions in time.
The line was used successfully against the invasion of the French
However with the second invasion of the French in 1794, the winter was very severe and the
flooded land and big rivers were completely frozen.
So in 1795, despite Dutch troops on
skates and sledges fitted with guns, the French were able to concur Holland.
picture shows the French crossing the ice.
When the line was flooded, the with dike like walls fortified towns
are like fortified defense islands in the water.
They protect the dikes which were running along the towns.
Guns were placed on the town walls, covering the dikes.
The dikes were the only roads, rising above the water surface.
So the dikes were the only roads, the enemy could use.
As you can see, the line was later on extended to the south
into a swamp area called "De Biesbos".
Now Holland was completely sealed off against invasions over
In that time invasions over sea were not usual and considered
to be very difficult.
The Dutch also had a very strong fleet with fast ships and
very able commanders that even took on the British fleet occasionally.
On other parts were no fortified towns were near dikes, that were crossing the waterline,
or pieces of high ground, small
fortresses were built as shown on this picture.
The Dutch used flat boats fitted with a cannon.
At night, they beamed or rowed the boat silently over the flooded land to the enemy
line at the other side.
Then they fired the gun and all of their muskets and vanished in the night or fog.
This picture shows the town Naarden, which is today the finest
example of fortified towns in the Netherlands.
The Dutch kept improving
the line in between various invasions and treads.
They fortified all towns in the line and built more and bigger fortresses
according to the latest strategic building views.
Also more sluice gates were made in the dikes, to improve flooding.
Between 1816 and 1824, the line is shifted a bit to the east, to
get the town Utrecht in the middle of the Netherlands, behind the line
However this was a bit higher ground, so more sluice gates
were built to improve flooding of this new piece of the line.
Also 11 new fortresses were built, at some distance around the east side of Utrecht.
Between 1840 and 1860, important fortresses were equipped with a round gun tower made
with very thick brick walls and buildings covered with earth, protecting the soldiers
against enemy guns.
Fortresses were also enlarged and equipped with more thick brick
and ground covered building.
The thick brick buildings and gun towers
could withstand direct hits from enemy artillery.
However the development of artillery went ahead on the development of the
When guns and grenades got powerful enough to destroy the
thick brick gun towers, the upper layer was removed and the remaining
part protected against direct hits, with a ring of ground covered
buildings at the enemy side.
The gun towers were now used to accommodate the soldiers and
as storage room.
When under attack, the guns and soldiers were now deployed in
field gun positions along the fortress walls.
The fortress on this draft picture is "Fort Honswijk",
which was also protecting the north side of the big river "De Lek".
Under, you see the gun tower with a protective ring of 180
There are many other thick brick ground covered buildings, used to store
field guns and ammunition.
Also there are many field gun positions visible along the
walls of the fortress.
The fortresses were built with the gun tower in the middle of the
dike, the dike was then led around the fortress, running away from the center
of the gun
So the guns had plenty of opportunity to blaze the enemy off the dike, if
they tried to get around the fortress.
The enemy had to use the dike
because anything else was flooded with water.
The fortress on this aerial photograph is "Fort Everdingen",
which was also protecting the south side of the big river "De Lek".
Here you see an aerial view of Fort Vuren at 4 km east of
Most of these big fortresses were not only protecting the
dikes, but also the big rivers.
Fort Vuren protected the North side of the big river Waal,
which changes name after passing Fort Vuren and is then called Merwede,
Opposite to Fort Vuren on the south side of the river
"De Waal" is fortress Loevestein, a fortified medieval castle,
protecting the south side of the river.
Fort Vuren started as an arrow-shape front protected position
for field guns, in fortification terms this is called a "Lunet",
see the point-shape in the left upper corner of the picture.
The gun tower that you see in the center left of the upper part of the
picture was built later and also the Lunet got an extension to the north
with a ground covered gun storage room, as you can see at the underside
of the picture.
Fort Vuren is in the summer season open for visitors. A boat tour starting in Gorinchem can be made, visiting the small fortress town
Woudrichem, the fortified castle Loevestein and Fort Vuren. Hikers can also spend the night at Fort
Vuren. Some other fortresses are also open for visitors.
Soldiers of the garrison of Gorinchem are exercising
modified "fortress guns" on the town walls of Gorinchem in the year 1935.
To be exact, the guns are positioned on the south-east side of
They are pointing to broadside-forward on the Merwede dike
On the picture on the left you see the flooding gate at Fort
Asperen (8 km north/ east) of Gorinchem in action in the year 1939.
The Dutch waterline was prepared against the German treat.
The picture on the right shows the result.
The landscape of Holland is covered with a maze of ditches and
When the land is flooded, these become invisible as well as the roads.
This forms a treacherous obstacle for enemy troops.
In strong winters, the defensive value of the Dutch Water Line was
decreased, when the ice on the big rivers and flooded land became thick enough for man and
light vehicles to cross.
However, the ice was cut open using special tools like the sawing
truck shown on the left picture.
Ice shelves were put upright to form obstacles.
Also a bit of water was let off the flooded land, which created weak spots in the ice.
Most of the Dutch were good skaters, what allowed the
troops to move fast when the flooded land was frozen over.
know the locations of the weak spots in the ice, they did create.
However, the enemy did not.
This picture was taken during the mobilization of the troops to positions in the
Dutch Water Line in 1939/1940.
|World War 2 started and on the 10 th of
May 1940, the Germans opened the attack on Holland with a lot of
airplanes. They were hunter,
bomber , troop-transport and flying boat type airplanes.
Also for the first time in a war, extensive use of paratroopers was made,
by dropping them around the government center behind the Dutch Water Line in
an attempt to capture airfields, government and queen to enforce a quick
Also paratroopers were dropped, to secure bridge heads at
traffic and railway bridges over the big rivers at the south-west of
Holland. A pantzer army was cruising blitzkrieg style through the south of
the Netherlands, towards the bridge heads.
This was all behind the The Dutch Water Line.
It was then clear, that air power and fast mechanized army's had reduced
the importance of the Dutch Water Line very much.
This page was updated on 16-02-13
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