The actual gate to the city was St Florian's gate, linked to the Barbican by a covered passageway. But the Barbican and the series of moats and walls which lead away from it, ringing the city, were the first point of entry to Krakow in the Middle Ages. Today, you still enter the Old Town of the city through the impressive Barbican.
Entry to the Barbican is included in the ticket for Brama Floriana gate tower and the other medieval fortifications. You can walk the remaining city walls.