Jacob's Island is one of Octavia Plumb's two Blighter strongholds in Southwark, a disease-ridden riverside slum. Clearing it turns it into a Rook stronghold.
Henry Green's information sends the twins into the Jacob's Island stronghold memory. Once the Blighters are beaten, the Rooks take over.
The stronghold leader complains that Octavia Plumb hides behind reinforcements and asks for volunteers to move against the Rooks. Keep lookouts quiet, as one raising the alarm breaks full sync, and stay unseen when you close in on the leader. Jacob or Evie can take it.
It is one of the two Blighter strongholds in Plumb's borough, the other being The Mint. Clearing both, together with her Templar hunts, bounties and child-labour liberations, prepares the ground for the Southwark gang war.
College Wharf
College Wharf is a Southwark loading dock on the Thames. You go there for Alexander Graham Bell in Cable News, freeing his crew and recovering seized cable reels, and later return to help set an ambush on Templar dynamite smugglers.
London Bridge station
London Bridge station is the oldest railway terminus in London, opened in 1836, at the southern end of London Bridge in Southwark.
Starrick Warehouse
The Starrick Warehouse is an abandoned Southwark warehouse used to hide stolen Punjabi gold in The Last Maharaja. In A Golden Path you help Duleep Singh hijack the gold carriage.
The Mint
The Mint is one of Octavia Plumb's two Blighter strongholds in Southwark. Taking it hands the site to the Rooks.