His best - known work is probably the large Town Hall of Amsterdam ( begun 1648 ) , now the Royal Palace in Dam Square .
About 1645 Van Campen designed the Nieuwe Kerk in Haarlem , a church that influenced Christopher Wren .
Van Campen 's best - known work is probably the large Town Hall of Amsterdam ( begun 1648 ) , now the Royal Palace in Dam Square .
About 1645 Van Campen designed the Nieuwe Kerk in Haarlem , a church that influenced Christopher Wren .