Found in this old crusader port are the remains of a fortress and the cathedral 'Our Lady of Tortosa'.

The fortress or keep in which the Templars locked themselves, when Saladin attacked, can be found at the south end of the old sea wall which the crusaders built. There is another inner citadel wall, which used to extend eastwards and then back southwards returning to the sea wall, although not much of this remains. However inside these walls are a banqueting hall and a chapel, which are still recognizable. 

There is another outer citadel wall and a third city wall, which can be followed before arriving to the cathedral that is also being used as a museum. After being used as a stable, and a mosque and Ottoman barracks the French renovated it and used it as a museum. This cathedral is by far the greatest show of religious crusader buildings in Syria. 

As you enter you can see that the Cathedral also had defensive purposes, through the corner towers. It is a simple Basilica in plan, with three aisles. Each aisle has four bays and an apse at its end; this represents the transition from the Romanesque to Gothic. There are massive arches with acanthus-topped columns. At the top end of the North aisle there is a headless bird thought to represent the third party of the Holy Trinity, the Holy Spirit. 

The museum section of the cathedral has a collection of objects ranging from the classical to the Arab periods. Mostly Syro-Phoenician and Greek artifacts, Roman glass, and funerary objects.