The castle is on the slopes of the hill overooking the port of Yialos and the town of Symi (Chorio), offering a breathtaking view of Symi Island, the Turkish coast, and the nearby Aegean island, including Nisyros with its volcano.
It used to be an ancient acropolis in the location and the ancient walls became part of the castle built there by the Knights of the Order of St John in 1407. 
It was never a particularly strong or impressive castle but was sufficient for the protection against pirate raids. 
The little bay is not visible from the open sea and the Knights kept there a fleet of light ships. A small arsenal built and repaired these vessels.
Over the years, the islanders acquired a reputation as carpenters which lasted until the early XXth century. 
The castle and the island remained at the hands of the knights until the Ottoman conquest in 1522. It features an emblem of the Knights of Saint John over the main entrance and is located at the highest point of the Upper Town.
There is also a small chapel dedicated to the Virgin Mary (Kyra Panagia). This chapel occupies the highest point on the castle and offers spectacular views of the towns of Chorio and Yialos and the Aegean Sea beyond them. The chapel is sometimes closed.

THE WAY FROM YIALOS (HARBOUR) TO THE CASTLE & BACK

• 800 metres of intence hill climb, or 20 minutes. You will need a total of 2,5 hours, allowing for stops to catch your breath, visit the Museum, have a coffe and a probably lunch.
• If you take a taxi from Yialos harbour to Chorio, walk to the Castle from the drop-off point, and then walk down the hill back to Yialos, you will save a lot of energy and 15 minutes.

From Skala Square on the harbour, climb the broad steps of the Kali Strata. Follow the signs through the alleyways. On the way to or from the Castle you will find coffe shops and restaurants.
Your uphill walk will last approximately 20 minutes. It is beautiful, but during the summer months it can be very warm. The beauty of the view will compensate you.
Alternatively, take a TAXI or a BUS  from the harbour to Chorio (8 min), and then walk to the Castle, which will take another 5 minutes. Click on the links for details on taxis and buses.
After your visit to the Castle, you can visit the very interesting Archaeological, Byzantine, and Folklore Museum (650m or 10 minutes from the Castle) and have a coffe or lunch at Chorio.
Your walk back to the harbour will be all downhill, much easier, and will last less than 15 minutes from the Castle, 20' from the Museum, or 10' from the restaurants.

Make sure you are back on time for your ferry's departure.

ENTRANCE:  Free

HOURS:   Open at all hours. The little church is sometimes closed.  

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