For sure you have to visit the tower of St. Nicolaus church. You will see the panorama of city which is really nice(with Slanske mountains). The gotic church itself is worth to see. Other churches to see-greek catholic church, ortodox church. And don't miss the synagogue. It's beatiful with museum inside. To mention is also old building of Zaborsky theatre.
A few kilometres outside the city of Presov (around 30 minutes by car) one can find this amazing castle. This is the largest castle in Slovakia. It was founded in 1209, wrecked by the Tatars in the 13th century and reconstructed in the 15th century. Although the castle burnt down in 1780, the ruins and the site are spectacular.
The highest enclosure contains a round Gothic tower, a cistern, a chapel and a rectangular Romanesque palace perched over the abyss. Instruments of torture are exhibited in the dungeon.