This is ''Het Schielandshuis''. It's the last buidling in the citycenter of Rotterdam that dates from the 17th century (build between 1662 and 1665). The building looks like a Hôtel Particulier (Dutch; stadspaleis, litarelly; city palace) from the outside, but it was build to house the water board of Schieland (hoogheemraadschap/ waterschap van Schieland), hence the name. It fulfilled this role for nearly 150 years. 

It was turned in a museum in 1841 until it closure in 2012 (due to budget cuts).

(Emperor Napoleon I stayed in this building from 25th october 1811 till the 27th with his wife Marie Louise. Tsar Alexander I of Russia visited the building a few years later, but he refused to set a foot in the room where Napoleon had slept)