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St Paul's Cathedral - One of the world's greatest landmark buildings, St Paul's Cathedral sits on Ludgate Hill at the highest point of the City of London. It's one of the most visited of London's tourist attractions.

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30 St Mary Axe -

Better known as The Gherkin, this is one of several contemporary buildings distinguishing London's modern skyline. Besides corporate tenants, retailers and restaurants operate from the site.

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Dr Johnson's House -

"When a man is tired of London, he is tired of life." So penned the great 18th-century writer, poet, and playwright, Samuel Johnson. His former residence is now a museum.

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20 Fenchurch Street -

Nicknamed "The Walkie-Talkie" because of its distinctive shape, this commercial skyscraper has a top-heavy form that appears to burst upward and outward. It's a familiar London skyline landmark.

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20 Fenchurch Street - The "Walkie-Talkie" features The Sky Garden, a unique public space that encompasses a stylish restaurant, brasserie, and cocktail bar.

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Leadenhall Market - One of the oldest markets in London, dating back to the 14th century and located in the historic center of the financial district, Leadenhall Market provides visitors with an authentic shopping experience, not least because of the stunning period architecture.

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Viaduct Tavern -

It can be thirsty work walking the Square Mile and if you only nip into one pub, make sure it's this one. Dating back to 1874, the Viaduct Tavern at 126 Newgate is one of the most beautiful ale houses in London town.

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122 Leadenhall Street - London residents like to name their modern buildings after everyday objects, it seems. This one is known as "The Cheesegrater" for its characteristic wedge shape.

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London Wall -

Remnants of the London Wall, the defensive wall first built by the Romans around their Londinium, can be seen within the Square Mile. Pictured is Bastion 14, which is overlooked by the Museum of London.

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Museum of London -

The museum is where to linger and absorb the history of the UK's capital city from prehistoric to modern times. Pictured is part of a 13th-century timber wall from the Thames riverbank at Billingsgate.

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The Shard -

Some of the finest and certainly the loftiest views of London can be enjoyed from the Shard's three viewing platforms, on floors 68, 69, and 72, but you'll need to book in advance for the privilege. The building stands in Southwark.

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Ye Olde Watling -

It's suggested that Sir Christopher Wren built this tavern in 1668 using timber from old ships. It's also been suggested that the thirsty architect that designed St Paul's Cathedral sat in one of the upstairs rooms.

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Southwark Cathedral - Dating back to around 1220, this is the oldest Gothic church in London. Check if there's a performance of choral music taking place—a truly moving cultural experience.

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Guildhall -

Dating back to 1440, this is the City of London's ceremonial and administrative center. Usually off limits to Londoners, the building opens its doors to the public during the annual London Open House weekend, usually held on the third weekend in September.

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Finsbury Circus - Finsbury Circus is the largest public open space within the City of London's boundaries. Leisure facilities include a lawn bowling green, and there's a bandstand nearby where small music concerts take place.

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Bank of England and the Royal Exchange -

Visitors to the museum inside the Bank of England (left) can pick up a gold bar as part of the experience... as long as they put it back afterward! Opposite stands the Royal Exchange (right) which houses a bar, restaurant, café, and a number of high-end retail outlets.

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Lloyd's Building -

Historic England describes the Lloyd's Building as "universally recognized as one of the key buildings of the modern epoch." It's been used on numerous occasions as a filming location: 'Mamma Mia!' (2008) and 'Proof of Life' (2000) are among the movies partly shot on the premises.

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Ye Olde Mitre -

They've been serving thirsty Londoners on this site at Ely Court since 1540, which makes this pub one of the oldest in the land. What you see today dates back to around 1773.

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All Hallows by The Tower - The oldest church in the City of London is over 1,300 years old (contrasted here against the "Walkie-talkie" building). Guided tours take in the crypt museum and Saxon and Roman artifacts.

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Postman's Park -

Hidden behind St Bartholomew's Hospital is this patch of green space that few bother to explore. The gardens enclose a Memorial to Heroic Self-Sacrifice, which comprises over 50 ceramic plaques commemorating ordinary people who died committing heroic acts.

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Punch Tavern -

The Punch Tavern on Fleet Street is named for the famous satirical 'Punch' magazine that used to operate out of nearby offices. Once a Victorian gin palace, this is still the place to order a G&T in convivial surroundings.

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HMS Belfast - Moored at Morgan's Lane off Tooley Street, HMS Belfast is one of London's most cherished visitor attractions. The World War II cruiser is a floating museum, having been retired from service in 1952.

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Royal Courts of Justice - Often serving as a backdrop for news bulletins and documentaries, these London law courts allow anyone to watch, most of the trials and hearings that are taking place (free of charge), except family cases.

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Staple Inn - This part-Tudor building survived the Great Fire of London, but was damaged during German bombing in World War II. Subsequently restored, Staple Inn can be admired from the street, and the public can also wander into the building's inner courtyard.

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Prince Henry’s Room - One of the few surviving buildings in the City of London dating from before the Great Fire of London in 1666, Prince Henry’s Room stands at 17 Fleet Street. The interior is currently only accessible when special events are held there.

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Paternoster Square - Set next to St Paul's Cathedral, Paternoster Square is the location of the London Stock Exchange.

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Barbican Centre - As well as its brutalist architecture, the Barbican Centre is famed for the Barbican Art Gallery and the Curve Gallery.

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Tower Bridge - Not strictly within City of London boundaries (its northern landfall is in the borough of Tower Hamlets), Tower Bridge nonetheless draws hundreds of thousands of visitors into the area, especially as it's located near the Tower of London.

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Tower of London - One of the UK capital's "must sees," this mighty stronghold encapsulates nearly 1000 years of royal history. Allow half a day to explore the building and its grounds.

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Monument to the Great Fire of London - Designed by Sir Christopher Wren to mark the Great Fire of London in 1666, The Monument stands near Pudding Lane where a bakery was the suspected source of the devastating inferno. If you want to reach the top, you'll need to climb 311 spiral steps for 61.5 m (202 ft). But the view is definitely worth the effort.

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The Square Mile -

And speaking of which, try and get a view of the Square Mile as night falls. The area takes on a totally different complexion as darkness encroaches.

See also: Fitzrovia, the London borough you've probably never heard of. 

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