Seriously good recommendation for a day out from West London - go for a walk on the London Loop trail. More info here.
A few weeks ago, at the Acton Carnival, Transport for London, with whom I have had a hate-hate relationship in the past, were giving out leaflets about various walking trails around London. The aim being to entice people to use their feet for leisure and maybe to start thinking about using them for work as well. Whatever you think of that aim these walks are fantastic judging by what I have seen so far. And they are free!
The London Loop is a series of nature walks on the edge of where countryside meets the capital, and if the other routes are even partly as good as the one I did last weekend they are fantastic.
Quiet, serene and surrounded by nature from the rabbits running around you to the birds. The closest route to Bush is route number 12 which you can see here. It means getting the central line to the end of the line at West Ruislip and then a bus to Uxbridge - and within minutes you're on the Grand Union Canal walking past locks and the odd ancient tea house. Its well worth a try - what have you got to lose?! Let me know what you think - here are some pics.