Complex sentence: The city, located at a rather privilegious area, among Nemea, Corinth and Arcadia also benefited by its proximity to lake Lerna, which, at the time, was at a distance of one kilometre from the south end of Argos.
Split into simpler sentences: The city, located at a rather propitious area, among Nemea, Corinth and Arcadia. It also benefitted from its proximity to lake Lerna, which, at the time, was at a distance of one kilometre from the south end of Argos.