The Sharon Beach National Park is situated between Wingate Institute to the north, and Gaash & Shfayim kibbutzim to the east.
The main attraction of the area are the kurkar dramatic cliffs over the sea. Don't get too close to the edge!
There are criss cross trails to navigate through, including Israel National Trail which enters from around Yakum intersection, and continues south all the way to Herzliya. You can walk all the way from Herzliya, or from the north, or find a way to the park in between (i entered from inside Gaash).
The best trail is the one parallel to INT to the west, the cliffs trail (hence the attribute, though it is not anywhere near GZ). Many great viewpoints for breakfast or sunset. The flora is typical to kurkar ridges and sand dunes, with some endemic species. Watch for birds of prey and crows enjoying the thermic current coming from the coast below, to glide in the air.
The cache - is hidden north of Gaash, next to Israel National Trail, in a small grove between trails. Stop at Israel national Trail mark, then continue west into the grove, over thick horizontal branches, to find GZ - unnatural pile of sticks - at base of 3rd (or 4th, depending how you count) tree on your left.