Andromache is near the battlement, or city wall, because Troy's fundamental civil engineering feat is the development of these high walls. She stands at these walls at a couple of moments. The first would be in Book 6, where she pleads with her husband, the brave Trojan warrior Hektor, to not go on the battlefield to fight Achilles. Her positioning near the wall is significant as she tells her husband not to go beyond it, outside it, and fight Achilles who has already killed men in her family and will proably kill him too. As fitting with most pleading in the work, her imploring does no good and the symbolic image of her positioning inside the city's battlements and Hector's outside of it reflects how, while there is obvious love and tenderness between them, the harsh condition of Classical warfighting also is present, creating a permanent barrier between both of them and their happiness together. Another reason she is near the battlement wall is in Book 22, where the duel between Hektor and Achilles ends with the great Trojan's death. Her running towards the battlement, the city wall, is done so to find that her husband has been killed, to which she faints. Another real interesting take on this question actually comes from Euripedes' work The Trojan Women. Detailing the horror of where Homer leaves off, Euripedes argues that Andromache is near the battlement, the city wall, because that is where the Achians threw her child, Astyanax, once the walls had been stormed. An excellent rendering of this can be found here, and one can see Andromache's placement at the battlement, a location where she loses both her husband and her son at the hand of Classical warfare and the will of the Gods'.