Gangsta's Paradise Coolio
A Victorian tunnel under the Thames - described as the 8th wonder of the world - opens to Londoners this weekend for the first time in 145 years.
The Thames Tunnel runs from Rotherhithe to Wapping and opened in 1843.
It was closed to pedestrians soon after and has since been used by passenger trains, but maintenance work means it's open to the public until Saturday.
But you'll only be able to go if you've got a ticket.