To supply water to Caesarea, the Romans built an extraordinary 23km-long system of canals, pipes and aqueducts and a 6km-long tunnel. A 300m section of the tunnel is now open for exploration, provided you don’t mind wading through 70cm-deep H₂O. Bring a flashlight, a change of clothes and footwear suitable for getting wet. Admission includes a one-hour guided tour. This is a great activity if you’ve got kids, especially on a hot summer's day (but it's not for the claustrophobic).
By road, Mey Kedem, near the religious community of Moshav Amikam and part of the larger Alona Park, is 18km from Zichron Ya'akov.