Portnahapple is a shallow sheltered inlet dive near Portstewart with parking close to the entry and enough structure to work well for easy training days. The middle is sandy, while the sides turn into rock walls, overhangs, and kelp, so the site feels simple at the entry but more interesting as you move out. It is a relaxed shore dive with plenty of marine life, especially when you want a short, low-friction north-coast session.