Amsterdam Geography

Amsterdam sits on the delta where the Amstel meets what was once an inlet of the North Sea, on ground that is almost entirely artificial.

Below sea level

Much of the city sits around two metres below mean sea level, and the wider Netherlands would be substantially underwater without continuous pumping. The land here is peat and clay laid down in a bog, drained from the Middle Ages onward by windmill and later by steam and electric pump, and the drained peat then shrinks and sinks, which means the pumping can never stop.

Piles

Nothing heavy can be founded on peat, so buildings stand on timber piles driven down twelve to twenty metres to a firm sand layer. The royal palace on the Dam rests on 13,659 of them, a figure Dutch schoolchildren learn. The piles last indefinitely while submerged and rot if the water table falls, which is why several streets of leaning houses exist and why groundwater levels are managed.

The canals

Not picturesque accidents but infrastructure: drainage, transport and defence, dug as part of a single planned expansion from 1613 in three concentric arcs, with the spoil used to raise the building plots.

The IJ and the harbour

The waterway north of the centre, once the route to the Zuiderzee and the open sea, now closed off by a dam and a barrier.

Water management

The city is divided into peilgebieden, zones each held at its own water level by weirs and pumps, because letting the level fall would rot the piles and letting it rise would flood the cellars. Amsterdam maintains around 1,700 bridges and continually dredges and re-walls the canals; a programme running to 2040 is renewing quay walls that are in places four centuries old and beginning to collapse.

Flat

The highest natural point in the city is a few metres. Everything is cyclable.