motorway A15 that goes to Rotterdam in westwards direction. Get off at exit 22 and follow the signs to Kinderdijk. The ride is about 100 km from Amsterdam.
By boat
You can also take the Waterbus ferry from Rotterdam (near Erasmusbrug) or from Dordrecht (on Merwekade). Take Route 1 and get off at Ridderkerk(De Schans). There you have to change onto Route 3, a smaller ferry to Kinderdijk that leaves every half hour. The pier is around 1 km from the windmills.
A single trip should take you around 45 minutes to an hour, depending on your point of departure and waiting time at Ridderkerk
