When his navy was within sight of Constantinople , he found the city gate closed and the entry into the Bosporus barred with iron chains .
The Rus ' leader , renowned for his oracular powers , refused to drink from the poisoned cup .
When leader 's navy was within sight of Constantinople , leader found the city gate closed and the entry into the Bosporus barred with iron chains .
The Rus ' leader , renowned for his oracular powers , refused to drink from the poisoned cup .