If the question is about the borders of the Empire, you can get amap of the Eastern Hemisphere and look at Egypt and Turkey in thewest and Central Asia and Pakistan in the East. That area spannedthe Persian Empire. Please see the Related Link with such a map.
If the question is referring to buildings and cities within Persia,they would have been very impressive to the people. The buildingswould be large boxes with large open spaces, collonades, anddetailed carvings. Please see the Related Link with reconstructionsof Persepolis, the Persian capital.