Construction Site Cave is in the Hudson Construction Site, west of Tarrey Town.
Cave Location
The Construction Site Cave is located at 3672, 1546, 0078 and has another entrance at 3736, 1532, 0080. It is in the Hudson Construction Site, west of Tarrey Town.
Cave Features
If you enter the cave from the western entrance, you will find the cave's Bubbulfrog on the bars.
To enter the area between the bars, you need to fall into the Construction Site Well at 3718, 1585, 0089. In the well, go southwest to the dead end, then look up to see a wall of boulders. Use bombs or other methods to break the boulders, then climb up.
There are more boulders in an archway. You can stand on the opposite side of the hole in the floor and attach a bomb flower to an arrow to shoot the boulders to get rid of them, or just hit the boulders with a claymore fused to a rock, for example. This leads to an area where you will find several Zonai capsules.