A few kilometers away from the south of Albert City was a small size fortress that was filled with guards, and the only way in was a small gate that could only contain one person at a time.
This fortress was known as the Bronze Gate Fortress because it was built around the Bronze rank dimension Goblin Paradise. The security of this place was as tight as it could get, and not even flies could enter without ringing magic detectors present in this place.
Not only this dimension gate but all of them were preserved like this so only those with the DEP could enter it and couldn't escape without paying their dues according to the Magic Union Dimension Diver Contract.
To this day, only a few have ever managed to enter or escape the Gate Fortresses in the history of the Magic Union. Not to mention all these cases revolved around the Silver or lower rank dimensions.
