Yehi'am Fortress National Park is an Israeli national park in western Upper Galilee on the grounds of Kibbutz Yehi'am, whose main attractions are the ruins of a hilltop castle in Jiddin.

The structure is based on the Crusader-time Iudyn Castle built by the Teutonic Order after 1220, destroyed by the Mamluk sultan Baibars sometime between 1268 and 1271, rebuilt and expanded by Zahir al-Umar as Qal'at Jiddin (Jiddin Castle) in the 1760s and destroyed again by Ahmed Jezzar Pasha around 1775.

Today the buildings include a watch tower with a lookout platform, mosque, and large vaulted hall.

[3] Trenches from Israel's 1948 War Of independence lay around the castle and can also be visited too.

Archaeological finds in the park but outside the castle precinct include the remains of a Roman fort, a Byzantine monastery, burial caves, stones inscribed with crosses and fragments of mosaic.