When the emperor's convoy was about a kilometer from the first gate, Big Sis and I hopped from the top of the Outer Wall and made an elegant, featherlight landing, so light that the two gatekeepers did not notice us until we landed in front of them.
The entry points of the walls were all twenty meters wide and ten meters high. However, they did not have built-in gates. That was why we had to build gatehouses for each entry point with a strong gate coupled with portcullis.
Each gate had two partitions that separated four lanes. From the right, outside the city, the first lane was for VIP vehicles to pass; the merged second and third lanes were for common vehicles as well as people; and the last lane was the exit point of a VIP.
Actually, there was a dungeon feature that added up to two additional entry points for each wall, just as the Imperial Capital had four gates. But we only add two more entry points on the Outer Wall for particular reasons.