If you read online about craft beer in the capital it won't be long before you come across a mention of the Bermondsey Beer Mile. This stretch of railway arches beneath the main lines out of London Bridge hosts such a concentration of craft beer breweries that it's become something of a weekend mecca for thirsty drinkers in search of the good stuff.
You can explore this all yourself, but for those of us who don't know London all that well - or just want to try something a little different - taking a guided tour can be a great way to get to know its ins and outs.
It's not always obvious where to go between one brewery and the next. A few of them are spaced quite far apart and the streets twist and turn beneath the tracks at times, so having a guide can provide a little peace of mind that you won't get lost once you've had a few beers.