The history of the Square Mile

Square Mile

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The Square Mile, also known as London City, is an area in the centre of the city which has become an affluent hub of finance and business in London. From ancient beginnings, the City of London has become one of the most culturally and financially relevant places on the planet. Home to thousands of global brands and international corporations, it is also a hotspot for millions of travellers and tourists.

Not only is London home to our 5 star city hotels London, it is also the location of the most prominent business operators in the world, which is why the area has become so famous. There is a deep history behind the city’s iconic financial district. We’ve put together this little history lesson so you can find out more about the area when you visit The Montcalm London Marble Arch.

What is known as the Square Mile started out as a half square mile, though that doesn’t quite have the same ring to it. The area was the first settlement site for Ancient Romans who colonised the area in 43 AD. Back then it was known as Londinium and was chosen for its convenient location next to the Thames River. It quickly became a very popular trading port for dealers and business owners thanks to the very useful trade routes in and out of the area.

During that time there was a lot of conflict in the area and after mounting defences, the Romans used Londinium as their primary base of operations in the wars against their enemies in the north. As part of the war effort, the Romans built the London Wall, a concrete structure that encircles the whole of the city. After the retreat of the Romans in 400 AD, the wall became redundant and fell gradually but parts of it can still be found standing today.


For centuries during the medieval period, the city grew in size thanks to the addition of wards outside of the walls. These city wards were given names such as Farringdon and Bishopsgate, eventually becoming part of what is now known as the City of London. This effectively doubled the size of the area making it the Square Mile we know today, or technically the square 1.05 mile we know today.

It was the Victorians who came up with the name Square Mile and they were also responsible for the huge developments that took place during the Industrial Revolution. Advancements in technology, politics, social justice and business operations helped the City of London evolve into one of the most important areas in the country.

Over the last century, millions of businesses and global companies have settled in the area that was once home to humble traders and local fisherman. Today you’ll find some of the biggest industry names and most influential brands in the heart of the city. The area has become a bustling place of trade and continues to bring in visitors from all over the world.