Invisible bridge glitch

The Invisible Bridge Glitch can be found on the level, Delta Halo. Once you begin, jump on the hill with the Grunt on the turret, jump up and up till you're on top of the map then go to the bridge area (If there are enemies around and Regret hologram is on the hologram, you messed up). Walk on the area the bridge would be (if it's there, go inside and unextend). Walk into the void where the bridge would be.

Invisible Bridge on Regret
There is also an invisible bridge glitch on the level Regret. First, progress as normal to the building where you fight Regret. Before the cutscene commences, get the gondola near the platform of the building. Once there, hurry and jump over the area the bridge is supposed to set up. If done right, you will activate the cutscene with the Master Chief walking on thin air. You will also be able to see the Marines if they were at the boarding platform.