
Two large parts of central London were closed to traffic yesterday. The closures were for two separate, but enormously important, events. Events highlighting issues which will affect all our lives radically in the very near future. One, in anticipation of the Copenhagen summit starting tomorrow, was the Climate Change rally from Hyde Park to Parliament Square. The other was Christmas shopping in Oxford St.
Obviously, I didn't want to wheel my bike amid an angry, shouting, jostling mob. So I went on the Climate Change rally (right).
As Mark Twain said, everyone talks about the weather, but nobody does anything about it. Well, here were a few of us - 20,000 according to the Met, 30,000 according to the Sunday Times, so probably in fact about 50,000 - trying to do, well, something. I don't suppose it'll do any good. I don't expect the Climate will take a blind bit of notice. It'll just go on changing anyway, regardless of whether or not the human chain actually did manage to link up all the way round the Houses of Parliament (I'm told there was a missing link around St Thomas').
It was all very good natured, sociable and chatty, with a broad spread of age ranges tending towards the mature. It seems everyone has an interesting story to tell: at one point I found myself invited, for instance, to a fetish club off the Walworth Road. Perhaps my prospective hostess mistook my bike's padlock and chain for something more exotic. But the Climate Change rally was lots of fun, and I thoroughly recommend these events, as you can turn up without actually having to commit yourself to anything. I joined somewhere in Piccadilly and followed sections of the march past Trafalgar Square and down Whitehall.
More fun than the march itself (which was a bit too full of shrill whistles for my liking) was the opportunity to cycle off-piste, on sections of road taped off from the marchers' route, but still closed to traffic. Runway-sized stretches of Piccadilly, Piccadilly Circus, Trafalgar Square (right) and Whitehall were both traffic- and march-free, and sheer delight to swan around on two wheels. Of course, now the march itself is over, the hard stuff, the real work, the genuine challenge, begins: all that darned Christmas shopping.



The bikes (right) are chunky, solid, one-size-fits-all, with three hub gears. There are chain guards to protect those stylish Gallic trousers, and lights that stay on all the time, Volvo-like, some strobing nervously like a warning light. They're pretty front-heavy, especially if you plonk a daypack full of one-euro plonk in the front basket, but they run smoothly and are a pleasant ride.
The multilingual terminals at docking stations show locations of nearby stations, and show how many bikes and vacant posts are available (right).
This is valuable advance info: you can find some docking stations empty, with no bikes to be had (right), especially around popular start-points such as a rail terminus.
Even if there are bikes, you might find some are out of action through punctures (right) or other problems. Their posts show this with a red instead of green light, and the system knows they're
Conversely, some popular destination docking stations might be full of bikes (right) and have nowhere to dock your bike back into.
Navigating Paris's one-way system isn't always easy, and you often find your nice separated bike lanes suddenly throw you out onto a cobbled traffic bedlam. But it's great fun, a delightful way of getting from A to B to C-cedilla, a genuine must-do, and is popular with locals (right: she 
Maybe the council could put archery-style targets on the remaining straight ones, to help drivers find the right contact point to create further new shapes? There's a Turner Prize waiting for someone.

