Dam square — in Dutch simply, de Dam — is Amsterdam’s best-known square. It is a handy central location from which to explore the medieval city centre. This is the site of the dam mentioned in the previous answer, though nowadays the erstwhile dam is no longer visible. Featuring the Royal Palace, Dam square often is the focus of events of national importance — as in the annual Remembrance Day (May 4) ceremonies which take place at the National Monument, commemorating those who died during the Second World War. By the way: do not refer to Amsterdam as "The Dam."