892-IV

From Memory Alpha, the free Star Trek reference.

892-IV is a M-class planet where evidence of Hodgkin's Law of Parallel Planetary Development was present as a parallel of the Roman Empire existed here.

Captain James T. Kirk and the crew of the USS Enterprise visited the planet 892-IV on stardate 4040.7. (TOS: "Bread and Circuses")

This planet is described in the non-canon Worlds of the Federation as being very similar to Earth, to the point that the shape of its continents and solar system are nearly identical. "Bread and Circuses" shows a very different continental arrangement.