Planned to be away at half term but DH not well so plans are all a bit in the air. Now thinking of different things to do including a day or two in London with the kids. They are 9 (DS) and 11 (DD) and want to make it a bit of an adventure by going on the train. We aren't too far from London. Have done the things like Buckingham Palace, River Cruise and Houses of Parliament in the past. DD loves a bit of history. Anyone got any recommendations of what's good for this age and if there are any deals out there? Otherwise gets really expensive.