The Warsaw Barbican was established in the 16th century as an element of the defensive walls of the Old Town. The Barbican was to increase the security of entry to Old Warsaw through the New Town Gate and to ensure the side defense of the neighboring walls. It had the form of a three-level semicircular bastion manned by fusiliers. It was designed by the architect Jan Baptist from Venice. Currently, in the barbican there is an exhibition of the Museum of Warsaw (open in the summer season) dedicated to the defensive walls of Old Warsaw.