You get the inside facts on this big city by erasing from its name one of two identical letters and then inserting two identical letters.
Name the city.

LONDON > 
LO( )DON >
LO(W)DO(W)N >
LOWDOWN

Another possible answer could be:
RUHR >
RUH( ) >
(T)RU(T)H >
TRUTH

The Ruhr is not a monocentric urban area like London, but like London it is an area composed of smaller towns, villages. And, seen on a map, Rurh could be considered a single city as there are no visible breaks between individual city boroughs. Of course, the initial T of TRUTH is not specifically inserted, but added at the beginning.

And, if you were from one of the neighboring communities of Luxembourg's Capellen and Holzem, not having adventured far, you might consider Mamer. the thirteenth largest town of Luxembourg, to be a big city:
MAMER >
MA( )ER >
MA(TT)ER >
MATTER

Edited on May 24, 2013, 1:04 am

Posted by Dej Mar on 2013-05-24 01:03:07