It amazed me to see the vast difference of opinion on gate locations of ancient Jerusalem, not to mention the shape of the wall. Those who provide maps of ancient Jerusalem do not inform us that their picture is hardly conclusive, but based on mere opinion which is itself based on difficult/confusing clues.
When Nehemiah recorded the re-building of the Jerusalem walls, he started at the Sheep Gate (3:1), on the north wall of the Temple Mount, and continued in a "circle." Keep in mind that in the ancient Jerusalem, the north wall of the city was in line with, and was therefore a westward extension of, the north wall of the Temple Mount. Also keep in mind that the city at that time extended about 3,000 feet south of the present south walls of the Old City, as far south as the Pool of Siloam.
Josephus allows us to be emphatic about Nehemiah going counter-clockwise in his Biblical report. For Josephus placed the tower of Hananeel on the north wall but west (i.e. counter-clockwise) of the Sheep Gate. Josephus called the Tower of Hananeel the tower of "Hippicus":
http://www.jewish-history.com/Palestine/walls.html
The Bethso location is where the north-west corner gate was located, which must then have been the "Corner Gate" referred to by Jeremiah (31:39). The article above also has this to say:
"Migdal" means "tower," wherefore it is evident that Migdol Pikus was the spot of the tower of Hippicus. It was clearly in the middle of the north wall, to the west of the Temple Mount's western wall. Also, for what it might be worth to us, the Tower was east of "Bethso," while the "gate of the Essenes" acted as the south-east corner of the City.
Nehemiah tells us that there was another tower, "Meah," between the Sheep Gate and the Tower of Hananeel. Thus, with the Sheep Gate in the north wall of the Temple Mount, the Tower of Meah would also be on the north wall, but, in relation to the Tower of Hananeel, closer to the Temple Mount...if not acting as the Temple Mount's north-western corner.
Nehemiah 3:3 then tells us that the Fish Gate was on the north wall as well, beyond (i.e. west of) the Tower of Hananeel. From Nehemiah 12:39, we can glean that the Fish Gate was right beside the Tower of Hananeel, just to the west of it, and there were two other gates west of the Fish Gate: the "Old" and the "Ephraim" gates (12:39).
According to 12:38, the "Tower of the Furnaces" was just around the corner of the north wall, on the western wall. Next upon that western wall (toward the south) was the Valley Gate (v 13) overlooking the Valley of Hinnom. Nehemiah 2:13 tells us that this gate was near the Monster Pool (Dragon and Serpent are alternative terms used), the latter being located outside the city on the south-west corner. But the Valley Gate is not said to be at the Monster Pool; the text may suggest merely that the two were next to each other. Thus the Valley Gate could have been, not at the south-west corner of the city, but more north, probably in the middle of the western wall. After all, it only makes sense that a wall as long as the western wall (about 2250 feet) should have a gate somewhere in its middle area.
We are told by Nehemiah that the Dung Gate was 1,000 cubits (about 1500 feet) away from Valley Gate, a long stretch that implies the turning of the south-west corner of the city...i.e. so that the Dung Gate is on the southern wall. Beyond the Dung Gate, toward the east, was the Fountain Gate, then a portion of wall along the Pool of Shelah (Siloam) overlooking the King's Gardens (these Gardens were at the junction of the Hinnom and Kidron valleys).
It's therefore made obvious that Nehemiah reports the repair of the walls in a counter-clockwise direction. But the importance in this exercise is the locating of the Tower of Hananeel on the north wall, in line with the north wall of the Temple Mount, for that Tower, and therefore that north wall, is said by Jeremiah to be the northern boundary of the Millennial City.
"Now of these three walls the old one was hard to be taken, both by reason of the valleys, and of that hill on which it was built, and which was above them, &c. Now that wall began on the north, at the tower called Hippicus, and extended as far as the place called Xistus, and then joining to the council-house, ended at the west gallery (cloister) of the temple. But if we go the other way westward, it began at the same place, and extended through a place called Bethso, to the gate of the Essenes, and after that it went southward, having its bending above the fountain Siloam, where it also bends again towards the east, at Solomon's Pool, and reaches as far as a certain place which they called Ophlas, where it was joined to the eastern gallery (cloister) of the temple.
The Targumist Jonathan Ben Uziel, a scholar of the famous Hillel the Elder (Sukkah, 28 a), lived in Jerusalem at the time of King Herod, who erected this tower in honour of his general, Hippicus, who had fallen in battle; consequently we must accept his explanation on this subject as correct, credible, and perfectly reliable. Now, on referring to the Tower of Chananel [Hananeel] of Jer. 31:38, and Zech. 14:10, we find that Jonathan renders it with Migdal Pikus, evidently Tower of Hippicus, whence it is perfectly clear that this tower must have been erected on the site of the ancient Chananel tower; for who could know more about it than this learned man, who lived on the spot when Herod built this structure?