nfitz
Superstar
Though that is the Oyster fare (about CAN$2.80). If you want to pay cash - you are out of luck though you can buy a one day pass for £5 ($9.40) - or use daily rate capping, which caps out at £4.50 ($8.45)... the bus is cheaper at £1.50 a ride
Though none of these let you in the tube. If you want to add in a short tube trip, it starts at £4.90 cash ($9.20) (or £2.40 with Oyster - $4.50) and can go as high as £8.50 cash ($14.10) and £7 ($13.15) with Oyster, depending how far you travel. It can be even higher if use use rail.