Burcht van Leiden (Fort of Leiden), Leiden (must see)

"Take the high ground" has long been a sound military doctrine. The viscount of Leiden, Halewijn I, understood this. He built the Fort of Leiden in 1060. But this was the Netherlands. There were no "high grounds." The fort was built as a keep, a round fortified tower. The structure's high ground was a motte, an artificial hill.

In the 11th century, the keep was rebuilt, first with volcanic tuff stone and finally with bricks. It was raised to a height of 30 feet by the 12th century. Ada of Holland, the daughter of Dirk VII, Count of Holland, took up residence in the keep. She and her husband, Louis II, Count of Loon, fought to keep her father's legacy.

The Fort of Leiden was captured by Ada's uncle William. Ada was evicted. In the 13th century, the castle became less and less important as a defense asset of Leiden. The city grew up around the base of the fort. The keep's interior, built against the inner walls, was partially dismantled. By the 17th century, it was merely a romantic symbol.

In 1651, it was decided to change the fort into a water tower for the city. The piping system leading to the city squares is still intact today. In 1662, a new portal, designed by architect Rombout Verhulst, was installed. Two other gates to the keep exist. At the south gateway, a plaque in Latin teaches basic grammar to Leiden students.