Located between Haifa and Tel Aviv (and perfect for a day stop) is Caesarea National Park. It is next to the sea and a former Roman City. Herod the Great expanded it and added bathhouses, temples, an amphitheater and roads etc. Now you can explore the ruins and see the stonework, pillars and more. The park itself is quite large and great for exploring. There are lots of nooks and crannies and places to run about and see. I took a picnic and enjoyed sitting in the sun and eating. There are restaurants and a great ice-cream stop too. You could also bring your swimwear and make it a beach day out as the water looked very inviting. I think it’s a pretty unique spot in Israel (considering it is Roman) and worth a visit solo, with friends or family!