A 10 mile run, from the centre of Amsterdam to the centre of Zaandam, including a run through the IJ tunnel. It is 10 miles, not kilometres, but miles. Why? Because that appears to be a nice easy distance - 16 km for the more modern among us.
Takes place in September, with some 30,000 runners. Has a tradition of corporate teams raising money for charity.
There is also a mini Dam totdam for kids.
website Check the left-hand column for an English link.