The Rock Bridge used to serve as a way to access the swamp in a vehicle, but, the bridge no longer works, and this cannot be done. The bridge used to be colored light brown in earlier versions of the game, but now it has the same coloration and material as the surrounding Rocks and Cliffs. The rock is about the size of one Snow Arch. Under the bridge is the Rock Bridge Cave, which leads to the widely-speculated Shrine of the Sight which recently has been solved using two numbered cubes. The bridge no longer works after multiple attempts on different servers.
The Rock Bridge has one main purpose: to get vehicles to the Swamp. The player used to be able to first bring dynamite through the Volcano and continue forward, carefully off of the side of the volcano (the side that faces the Safari). Then, the player must place Dynamite at (most preferably) the middle of the rock. The rock bridge will then slide down over the Rock Bridge Valley, just over the Rock Bridge Cave. This has been tested and as of 3/17, it has been confirmed that it no longer works. The player can then bring their vehicle down to the Volcano entrance, hook up their trailers, and continue to the swamp. The player must stick to the gravel road until it comes to a stop. From there, the player must look to the right for a small ramp that leads down the cliff. Then turning to the right at the bottom of it, the player will then come across the Swamp Cavern and will then arrive at the Swamp. After collecting desired wood and/or materials, the player will then drive out of the other end of the swamp and follow a smooth mountain valley that leads to the Safari. Or they can use the bridge to go back the way they came. This bridge tends to glitch a lot, so it is not the recommended way of getting to the Swamp.It is to be noted that after several minutes, the bridge will crumble into little segments and it will despawn, needing to be blown up once more. Also, it is not recommended to put dynamite on the bridge as it will fling the bridge off its resting spot.
On October 29, 2016, some people have figured out that by jumping or shift-locking at the bridge, it will eventually roll off. This reveals that the rock bridge is unanchored and the force of the dynamite pushes the bridge down, not a script detecting detonation of dynamite.
As of September 16, 2017, the bridge does not work with dynamite. It has been confirmed on multiple servers with multiple attempts.