Blue Borough is slang for the 'London Borough of Lewisham' in South East London.
Lewisham is called 'Blue Borough' because:
The logo for Lewisham is blue.
The dustbins are blue.
The street signs are blue.
Areas in blue borough are:
Downham, Grove Park, New Cross, Brockley, Lee, Sydenham, Lewisham, Forest hill, Hither Green, Ladywell, Blackheath, Deptford, Catford, Bellingham.
Blue Borough is home to several gangs, inclding Ghetto Boys, Anti Shower,Deptford Boys, Young Deptford Boys, Hood Bangerz, Deptford Marliez, Young Deptford Marliez, Team Brockley, Turnham Gang, The Money Makers, Young Money Makers, Black Mafia, Monson Bloodset.
Blue Borough is home to notorious housing estates:
Woodpecker/Milton Court Estates, and many more.
Blue Borough postcodes include:
SE8, SE23, SE12, SE6, SE26, SE14, SE4 AND A BIT OF SE3
A: I'm from Catford.
B: That is Blue Borough innit?
A: Yes it is.