'What new tube map?" grunted the official stationed at King's Cross, when I asked for a copy of the design classic that shows the lines of the London Underground.  "Your imbecilic and geographically illiterate new diagram that's wiped the River Thames off the map," I replied, in my head at least.  By removing the blue sweep of the Thames from its latest map, Transport for London has not just messed with the design classic created in the early 30s by Harry Beck. It has removed a vital orienting point, besmirched the capital's history and, worst of all, annexed the separate kingdoms of north and south London.  OK, so non-map-nerds may argue that the tube map never exactly reflected geographical reality. And if cartographers put points of interest on the tube map, where would it end? Big Ben? The Emirates stadium? Aberdeen Angus Steakhouse?  But that misses the point. The Thames is the reason London is here. No Thames, no Londinium, no largest city in Europe, no, er, boat race. Rivers define great cities. We want to know the closest stations to the Thames's banks, to taste its salty breeze. We crave a pub by the water where we can watch the sun set over plastic bags bobbing in its brown waves. The Thames is the oldest line in London of all – and we still travel on it by boat.  King's Cross does not yet stock the new tube map but when I reach Leicester Square, tourists are peering at a large version of the redesigned map. They look newly vulnerable, unable to tell if a station falls in the badlands or the cradle of civilisation (I wouldn't dare suggest which side of the river is which). Interestingly, the Ikea advert that appears on the bottom of the large maps in stations these days has survived. But the River Thames doesn't pay TfL any money, so it is gone.  TfL says it "wanted to remove clutter" – and, to be fair, it has erased much of the pointless "information pollution" added to the map over the years (instructions about interchanges, closures, and zigzags where lines intersect, making it look as if the trains must navigate a zebra crossing). But please, bring back the Thames. Without it, our great capital looks emasculated and featureless. This is not a tube map – it's a pointless diagram.
The new map of the London underground hasn't got the river Thames on it. How wrong is that?