Caesarea National Park has two entrances: the northern (Crusader gate) entrance, which takes you through the Crusader ramparts to the harbour and its restaurants; and, 600m to the south, the southern (Roman Theatre) entrance. Coach tours often drop visitors off at one and pick them up at the other, but if you'd like to circle back to your car, the northern entrance is a better bet.
A full-price ticket gets you into the Roman ruins (situated between the two entrances) and three multimedia presentations. A harbour-only ticket, available at the northern entrance, gets you access to the harbour area, including its restaurants, and the Crusader city but not the Roman city. After the park's closing time, entry to the harbour – whose restaurants and bars stay open until late at night – is free.