There are all sorts of guides to London pubs but as far as we can find, nobody has ever pinpointed the city's frontier pubs: those places which are the furthest north, south, east and west.
To add a bit of fun to the task, we decided to visit them all in one day. Taking public transport meant an average of a two-hour journey time between each spot. With an average distance of around 25 miles between each, it's certainly a drawn-out crawl.
Here are London's furthest-flung pubs: the final places you can enjoy a pint before crossing the boundary and leaving the capital behind.
The Fox, Coulsdon Common, CR3 5QS
How to get there: 466 bus from Purley station to Coulsdon Common Fox stop
We have to travel through a lot of south London suburbia to reach The Fox. The 466 bus, which stops very close to the pub, goes all the way from East Croydon station, but it can also be picked up at later stops along the line such as Purley if you'd rather not spend 40 minutes on a bus.
Located at the edge of Coulsdon Common, The Fox dates from the 18th century. Inside it's pleasant enough with wooden beams, stone floor and a fairly run-of-the-mill range of beers, such as London Pride and Doombar. It's part of the Vintage Inn chain of pubs, so the menu is similarly humdrum. There are a fair few people already here when we arrive at lunchtime.
Given its proximity to the greenery of the Common, it perhaps isn't surprising The Fox has the air of a country pub. The common itself is a small interruption in the suburban sprawl which returns immediately due south, as the Surrey town of Caterham.
The Kings Arms, 593 Bath Road, Longford, UB7 0EG
How to get there: 423 bus from Hatton Cross tube to Heathrow Close stop.
The bus journey from Hatton Cross takes us past aircraft hangars and various other Heathrow ancillary buildings, with a strong smell of aviation fuel throughout.
The Kings Arms is at the end of Bath Road in a very small village called Longford, immediately north of Heathrow Airport. This small row of houses in the shadow of one of the world's biggest airports makes for a unique atmosphere.
Given its proximity to the airport, the pub and every other building in the village will be flattened should the Government decide in favour of a third runway at Heathrow.
Investing in renovating a pub with the spectre of the Heathrow wrecking ball hanging over it is never going to be good business sense, so the pub's interior is less than remarkable. Food-wise it’s got an Indian menu, while on the drinks front there are no ales on tap. It also has a small garden which faces the airport buildings so doesn't have the most scenic view. It's very quiet here when we visit, but then a pub a stone's throw from Heathrow is few people's idea of a good way to spend a mid-week afternoon.
The Plough, Cattlegate Road, Enfield, EN2 9DJ
How to get there: Great Northern rail from Moorgate/Finsbury Park to Crews Hill
Leafy Crews Hill is home to Greater London's most northerly railway station. Even the road to the pub — Cattlegate Road — sounds rural and is home to what must be London's biggest collection of garden centres in one area. We counted at least five on the short walk from the station to the pub.
The Plough is a friendly pub with a small bar area and a more spacious dining area, as is the case with many suburban pubs these days which are focusing on the food trade. Owned by the Hertfordshire brewery McMullens, it stocks their in-house ales including Country Bitter and their AK bitter. We also ate here, paying £8.50 for a cheeseburger.
As you might expect, The Plough has a large garden but — more surprisingly — also its own small petanque area.
The Old White Horse, Ockendon Road, Upminster, RM14 3PS
How to get there: 370 bus from Upminster station to Fen Lane stop.
The built up environment around Upminster quickly morphs into open countryside as the 370 bus makes its way towards the pub on the quiet Ockendon Road. To give you an idea how far out this is, on our way we passed the psychological barrier that is the M25.
The Old White Horse is a cosy, old-fashioned pub inside with cut glass mirrors and old adverts for Pears Soap on the wall. The pub does food and the dining area is set out in a traditional manner which reminds you of a traditional English B&B. There are a couple of ales on tap in the shape of Woodforde's Wherry and Adnams Broadside.
The Old White Horse's real selling point is its massive garden. It spans a good way from the pub out into the distance, bordered by a large open field. We get here just before dusk set in and enjoy a pint in the garden as the light fades. The pub had been pretty quiet inside and as we decide to venture in for a second pint, we find them to be closing up. And so our journey home begins.
Is it worth it?
Visiting London's frontier pubs is great fun. OK, it's not a beer lover's, or foodie's, idea of heaven. But it's the journey that counts. And, of course, the extreme locations.
Three of the four are situated in very green and pleasant surroundings which feel a million miles away from being in a capital city. The Kings Arms at the Western frontier is the obvious exception — right on the doorstep of the world's sixth busiest airport.
The crawl also serves as an illustration of just how vast London is: it's just under 30 miles between The Plough at London's northern tip and The Fox in the south, while the distance between The Old White Horse in the east and the Kings Arms in the west is 37.5 miles.