The Mint is one of Octavia Plumb's two Blighter strongholds in Southwark. Taking it hands the site to the Rooks.
A lead from Henry Green sends the twins into The Mint stronghold memory. Clearing out Plumb's Blighters turns it into a Rook stronghold.
The stronghold leader rallies his men, passing on Octavia Plumb's call for volunteers to fight the Rooks. Deal with lookouts first, since the full-sync condition fails if one raises the alarm and brings reinforcements, then find and burn the heist plans before taking out the leader. You can play it as either twin.
Plumb's grip on the borough also rests on her Templars Phillip Beckinridge and Myrtle Platt, the Blighter targets Anna Abramson and Albie Vassell, and three child-labour sites: Blackburn Bellows, Hightower Coal and the Southwark Spinning Mill. Taking The Mint is one step toward 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.
Jacob's Island
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.
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.