Complex sentence: The Royal Castle (Polish: "Zamek Królewski") in Warsaw is the royal palace and official residence of the Polish monarchs, located at the Plac Zamkowy, at the entrance to the Old Town.
Split into simpler sentences: The Royal Castle (Polish: "Zamek Królewski") in Warsaw is the royal palace and official residence of the Polish monarchs. It is located at the Plac Zamkowy, at the entrance to the Old Town.