Welcome to the Yarkon Bridge, yes there are many other bridges over the river, but this one is The bridge, and is nicknamed the Yarkon Bridge, on it goes highway #2 all the way to Haifa.
On its eastern side you can see two bluish arches, back in the days brave youngsters used to climb the arches. Don't do it! :)
Cache is located in the tunnel, under the pedestrian bridge on the western side, north of the water. Right off Israel Trail and Yam to Yam Trail. It contains just a log. Please be mindful not to drop it behind, when attaching back the magnet. BYOP
Note: photos will give you the hiding place. GZ is right next to the bike trail. So be careful and don't forget yourself after finding the cache and putting back. Watch for bikes passing before returning to the trail.
About the geo-trail: The Tel-Aviv - Jerusalem Bicycle Trail is a 120+ km long path connecting Jerusalem (abbreviated in Hebrew as Y-m or Yam) to the Mediterranean Sea (in Hebrew: Yam). If you want to read more about it, you can enter Yam to Yam Geo-Powertrail: 0 km (GC3TXQD)