Don't forget to bring your camera to capture the beautiful cascades of Harbiye Waterfall. If it's raging, you may be able to feel the mist on your face.
When you've spent some time at this Defne cascade of water, why not check out Antakya Archaelogical Museum, Habibi Neccar Mosque, and St. Paul Orthodox Church? They're not too far from Harbiye Waterfall and also a favorite with many travelers.