This sounds silly but what are the prices of the underground as I don't live in London!
It depends on whereabouts you’re travelling to or from; the Underground in London is split into Zones, and how far out from the centre you are determines what Zone you have to pay to travel from.
Most of the SitC activities won’t stretch any further than Zone 2, but just in case, if this is your first time in London then we advise you familiarise yourself with the Tube system before SitC.