The Sparta Stadion, nicknamed Het Kasteel (Dutch pronunciation: [ət kɑsˈteːl]; "The Castle"), is a football stadium in Rotterdam, Netherlands.

A famous incident took place at het Kasteel in November 1970, when Feyenoord goalkeeper Eddy Treijtel took a goalkick and shot a passing seagull down from the air.

The first was on 5 June when host nation Netherlands defeated Belgium 3-1 while the second was three days later when the Dutch team tied Chile 2–2.

That name was soon replaced by the present Het Kasteel ("The Castle"), which had already been the popular nickname for the stadium ever since it was built.

Van Heelsbergen opened in this building a Sparta museum (and an outlet of Hans Textiel).

The lowest priced tickets for home fans are to be found in the Denis Neville Stand.