twee halen een betalen

Rijksmonumenten challenge #3-4.
When I see the "twee halen een betalen" sign in shops I assume it means "buy one and get one free". So today, you get to see 2 rijksmonuments for the price of one :)
"The star" (foreground) and "the lily" (background) are octagonal wind mills located on the Kralingen Lake Rotterdam. The two mills still ground snuff and spices. The Star is built on the foundation of an earlier mill of the same name, which burned down in 1865. The Lily was built in the old Kralingen in 1740 and was called The Donkey / Ass (can someone confirm?). In 1840 the mill was moved to its present location.
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