The Marsdiep is a deep tide-race between
Den Helder
Den Helder () is a municipality and a city in the Netherlands, in the province of North Holland. Den Helder occupies the northernmost point of the North Holland peninsula. It is home to the country's main naval base.
From here the Royal TESO ...
and
Texel
Texel (; Texels dialect: ) is a municipality and an island with a population of 13,643 in North Holland, Netherlands. It is the largest and most populated island of the West Frisian Islands in the Wadden Sea. The island is situated north of Den ...
in the Netherlands, and running southwards between sandbanks. That gap connects the
North Sea
The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian ...
and the
Waddenzee.
Around 1000 AD and before, much of the modern Waddenzee and
IJsselmeer
The IJsselmeer (; fy, Iselmar, nds-nl, Iesselmeer), also known as Lake IJssel in English, is a closed off inland bay in the central Netherlands bordering the provinces of Flevoland, North Holland and Friesland. It covers an area of with an ...
was land and the Marsdiep was an ordinary brook. An early form of its name is Maresdeop, a name probably related to modern Dutch ''moerasdiep'' ("swamp deep"). During the
All Saints' Flood of 1170, the sea broke through the original dune barrier and created the channel.
The ''Marsdiep'' was in the
age of sail
The Age of Sail is a period that lasted at the latest from the mid-16th (or mid- 15th) to the mid-19th centuries, in which the dominance of sailing ships in global trade and warfare culminated, particularly marked by the introduction of nava ...
in English called ''the'' Texel, in distinction from the island of Texel.
Straits of the Netherlands
Texel
Den Helder
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