But there is also a rather steep ri

But there is also a rather steep rise in the terrain right from the city itself in a north-western direction before one reaches the plateau, rendering Syracuse vulnerable to attacks launched by an enemy who has climbed the northern rim of the slanting elevation and crossed it in a southward direction. For, though the rim of the plateau falls off steeply on all sides for about 10 to 15 meters to the next lower terrace (see PLATE I: an exampl from the northern rim), it has five access points alone on its northern slope, and the northern rim is not visible from the city. This is one major problem the Syracusans feel they have to deal with...they believed that, if the Athenians were prevented from becoming masters of Epipolai, a steep area lying right above the city, they themselves would not easily be walled off (by a siege wall), even if they should be defeated in a battle. Therefore they intended to guard the (northern) approaches, to prevent the enemy from climbing up at these points tunnoticed; for nowhere else (by no other route) would they be able to (scil. climb up without being noticed) (6.96.1)The threat of an Athenian siege wall or circumvallation has been on the Syracusans' minds for a long time. Already during the preceding winter they have extended their ciry wall north of the city in a west-east line along the whole stretch along the south side of Epipolai (including a bulge to the west so as to enclose the Temenites with the sanctuary of Apollo) in order to make it more difficult for the Athenians to surround the city on land with a siege wall (75.1): the longer the Syracusans' own defense wall, the longer the enemy will have to build their siege wall (6.96.1).