[ElcinBoris]

18:86
Until, when he reached the setting of the sun, he found it setting in a spring of dark mud, and he found near it a people. Allah said, "O Dhul-Qarnayn, either you punish [them] or else adopt among them [a way of] goodness."

i dont understand arabic so correct me if i am wrong, but reading this in english sounds like to me that dhul qarnayn walked till the sun started setting and at the point that it started setting, he reached a place of dark mud where he found some people.