We've all been there. You stayed for one quick pint but then all your mates were moving onto the next bar, and it would have been rude not to join them for a cocktail. You spend the night hopping between bars and more pubs and "this really cool whisky den Pete knows about," before closing your supposedly quiet night with a large lamb doner.Next time you find yourself nursing a post-pub crawl hangover, spare a thought for the Black Country Ale Tairsters, a West Bromwich-based charity pub crawl group who just reached their 20,000th pub.Unsurprisingly, it took a lot more than one particularly rowdy night in the West Midlands to reach this milestone.The Black Country Ale Tairsters (which means "tasters" in Black Country dialect) was founded in 1984, when a group of guys decided to visit the 300 ale houses listed in a map published by Wolverhampton brewer Banks's. They then expanded their crawl to the 12 Midlands counties and Wales.The group asked each pub landlord for a £1 donation and since starting, have raised £24,000 for charity. And, of course, they've gotten through a fair few drinks in the process. Co-founder Peter Hill told the BBC that he had consumed 46,632 pints and made notes on each establishment visited. He said: "On every pub crawl, everything is documented—from the beers in the pub to the decor."Sounds a lot more civilised than the kinds of pub crawls we find ourselves on.