Is that a tourist trap or a danger warning, I don't know but it is important.
I have visited Ioanina on several occasion and the first time in 1975. Ioanina has developped mostly before the car era. It could accomodate a limited number of cars in its streets. Therefore with an increasing number of citizens owing a car plus visitors'cars , year after year, it has been more and more difficult to drive in Ioannina and even more to park, even just for a stop.
In a large part of the city center, stone balls (or metal, I have not been able to check as I could not stop!) are fixed every 3-4 meters on the side walks to impede parking and leave it for pedestrians. The fery few parking spaces are engaged all the time. It is even impossible to stop for a minute in front of one of the hotels.
My advice : park outside of the city (which can be far away, but there are busses), take a hotel outside Ioannina, for example in Perama or better just outside Perama and take a bus
The CASTEL OF IOANNINA is one of the oldest of its kind in our Country. It was built by the Emperor Justinian in 528 AD. It's the oldest Byzantine Castle and it is contemporary to those of Didimotiho and Monemvasias.
It consists of four parts: the surrounding wall, the N.W. acropolis with the 'Aslan Pasha' mosque , the N.E. acropolis with the 'Its Kale' mosque and last the town. The area that is enclosed by the walls is about 190,000-200,000 sq.m., and its length is about 1800-2000m.