This detail from a British map shows how the
Russian defensive works crossed from the Redan (Bastion 3) and Barrack Battery
(Battery 3) to the Flagstaff Bastion (#4) and its outer work, The Crow's Nest.
Note that the Peressip batteries were right at the edge of the inner harbor,
which practically split the Russian lines in two. But both Batteries 3 and 4
were on very steep hills and had good cross fire over the Vorontsov ravine. The
British 3rd parallel with several artillery positions is on a lower ridge
between the Redan and Flagstaff Bastions.