BOOZE CRUISE

Britain's highest pub is the Tan Hill Inn, 1,732 feet up on a lonely Yorkshire moortop. But where's the lowest...? Rob Ainsley cycles between the two. Downhill, obviously

Ah, the pub, that British cultural icon. There are over 45,000 of them, and I've biked to many of the most notable ones. Among the oldest are Ye Olde Trip to Jerusalem in Nottingham or the Bingley Arms near Leeds. The latter is best for authentic period features, such as having no cycle parking. The smallest pubs, on the other hand, might be the Nutshell in Bury St Edmunds or the Signal Box in Cleethorpes. Buying everyone in the pub a drink won't come cheaper. The biggest pubs include Brewdog's The Sidings in Waterloo and Wetherspoon's Moon Under Water in Manchester; by the time you get from bar to table, you've finished your pint.

And I've cycled to various olde-worlde, parlourand timewarp-pubs - the Sun Inn in Leintwardine; Tucker's Grave in Somerset; Birch Hall Inn at Beck Hole in Yorkshire, and more.

However, the top pub of all-in altitude, if not more - is the legendary Tan Hill Inn. It's at 1,732 feet, or 528m, on a lonely North Yorkshire moortop above Swaledale: a thrilling ride up from Keld, and a fabulous freewheel down to Reeth. It served thirsty miners in the 1700s, but the coal and the workers' cottages are all gone now. The pub's now an isolated wonder over 10 miles from the nearest proper shop, and has featured in books, telly ads and myriad blogs.

But the lowest pub? That's open to debate. I've ridden the drained, sunken fens south of Peterborough, nearly 3m below the zero-line in Newlyn that's the Ordnance Survey's 'sea-level' reference point. But OS maps suggest no pub in those fens has a negative altitude. So we're looking for something by the sea. There are plenty of shoreline pubs and beach bars round Britain's coast - but which would count as 'the bottom one'?