Answer
Netherlands's lowest point is the Zuidplaspolder with an elevation of -6.76 Meters above sea level.
The Zuidplaspolder is a polder in the western Netherlands, located northeast of Rotterdam, Zuid-Holland, neighbouring settlements such as Zuidplas, Zevenhuizen, Waddinxveen, Moerkapelle, Gouda, Moordrecht, and Nieuwerkerk aan den IJssel.