The train into London this morning was full of green padded body warmers (gillets?). The farmers were revolting (their words, not mine) - protesting for their liberty and their livelihoods. 400,000 people descended on London and television news anchors called it the biggest demonstration in British history.

The MP Liam Fox was marching with them. I joked that he was probably protesting against fox hunting. People looked at me strangely.

So, before I left I packed my camera in my bag, thinking I might be able to get some good photos of farmers protesting (cow dung being thrown at the gates of Downing Street - that sort of thing), and after the show headed south out of ITN towards Holborn. I cut down to Fleet Street, then towards the river, stopping on a bridge to watch the long snake of marchers pass noisily beneath.

I descended the steps to the road and walked against the flow as far as St Paul’s, then giving up any hope of the marchers doing something interesting crossed the Millennium Bridge to the Tate Modern and went inside.

I’ve been inside the turbine hall before, but still the scale of this building is breathtaking. The whole thing seems to tower above you, and its grandeur makes it such an appropriate choice for a gallery of modern art.

Inside there was the usual tat - large canvases of just a single colour, a pile of 120 bricks, a glass of water on a shelf - but hidden among them were some genuine treasures. Two real stand-out installations were ‘Cold, Dark Matter: An Exploded View‘ by Cornelia Parker and ‘United Kingdom‘ by Layla Curtis.

While ‘Cold, Dark Matter…’ was spectacular (a garden shed full of junk blown up by the army, and then the broken pieces hung from the ceiling), ‘United Kingdom’ was far more clever. When you first look at it, it’s just a map of the UK. Look closer, though, and you see that the artist has made it by cutting up a road atlas and sticking it back together with Scotland made up from bits of England and Wales, while England and Wales are made from bits of Scotland.

After looking at it for a few minutes you then realise that it’s even cleverer than you thought, as all the roads actually match up, so if a car were ever to follow these new routes it could find itself driving from Colchester directly into Slough without once ever turning off the motorway.

I guess it comes across better when you look at it than it does when you try and describe it, but I was disappointed they didn’t have any posters of it in the gift shop.

I sat in the window on one of the upper floors while my feet recovered, then set out along the South Bank again, past the Globe to London Bridge, then north and east to the Tower of London. From there to Liverpool Street and eventually, with feet and knees groaning, onto a train home.

I feel I’ve walked miles, and fully excuse myself a trip to the gym today. I came home and soaked in the bath, listening to LBC, then flopped in front of last week’s taped episode of White Teeth. Very good, although I’m not convinced I’ve missed anything by not reading the book.

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