The Iteration road is a diagonal road which starts somewhere East of the home page center (it's beginning has already been overwritten) and continues south-east. It is unique in a way that each of its segments is labeled "Iteration (number)", with the number increasing with each segment. That's also how it got its name. It has been theorized that it ends by iteration 10 000, however it actually ends sooner and is followed only by blank space. There are also multiple "fault lines" in the road, where it is suddenly moved by couple characters and its iteration count fluctuates widely.
Most likely it has been created by a test script that used the iterations count as a debug output