Originally Posted by
Gagravarr
You might want to double-check your flight details - Heathrow terminal 1 closed a few years ago!
I'd suggest Piccadilly line tube to Hammersmith, change to District line to Blackfriars. Then, walk 5 minutes along the road to outside St Pauls Cathedral, take a look outside, then take the Millennium bridge over the river to the Tate Modern with great views as you go over!
This. My favourite bit of London. Plenty of lunch options as you wander back along the south bank of the Thames, then cross over via Hungerford Bridge to Embankment and then take the District and Piccadilly line back to LHR