The Kinderdijk windmills are must-see sights for tourists. They're also functioning windmills that are helping to keep Holland above water.

The windmills of Kinderdijk create a unique and lovely landscape as well as an interesting and educational experience. But I admit my favorite part was a visit inside one of the quirky windmills ...

Tourists on a boat tour windmills lining Hooge Boezem van de Overwaard canal at the UNESCO World Heritage site in Kinderdijk, Netherlands.

About 500,000 people visit the Kinderdijk windmills each year, about 300,000 of buying tickets to take the tours.

In this Feb. 14, 2017, file photo, tourists on a boat tour windmills lining Hooge Boezem van de Nederwaard canal at the Unesco World Heritage site in Kinderdijk, Netherlands.

About 300,000 people buy tickets to visit the Kinderdijk windmills each year, with about 500,000 more walking through the area without taking the tours.

About 500,000 people visit the Kinderdijk windmills each year, about 300,000 of buying tickets to take the tours.

The windmills at Kinderdijk were built in the mid-1700s as a way to clear water from the low-lying landscape of the western Netherlands. Sometime in the 1950s, the millers and water board members ...

About 300,000 people buy tickets to visit the Kinderdijk windmills each year, with about 500,000 more walking through the area without taking the tours. Kinderdijk has plans to build a new visitor's ...