Thank you all so much for great suggestions. The Starbucks info is particularly useful Blondie, for future reference too. I particularly like the fact that you have all suggested things to keep me interested all day too!
Help from any all well-informed MNers, please! I have volunteered to look after my 5 month old grandson in London at the beginning of November, while my daughter goes to a work training day in the City (Fleet Street). She is still breast-feeding so I need to keep close enough to meet her every 3-4 hours. I can't keep the poor boy in his pram all day - any bright ideas of places to go / see, good places for nappy changing? Please?