Good ferry site Zimzum - the wealth of things to see at that part of the Thames is amazing.
The return route after the ferry crossing brought plenty of sights, showing that there is a vast amount of work underway around Canary Wharf, a lot of rubble around - and a scale of buildings which contrasted nicely with our tour, then exit from the spacious Greenwich Park.
Then suddenly, a plane slips from the sky and floats gently into City Airport, the O2 Dome nudges a reminder of millenium times and new meets old as we head inwards!
The river is majestic - the crossing offering yet another vista beyond the Thames Barrier.
Still thinking of those people slugging away on their charity ride...hard going in that heat.