We get off the tube at Waterloo Bridge because Westminster has been closed due to the huge numbers, and we walk over the bridge towards the start point. Already we can see many thousands of people marching ahead of us along the Embankment.
An eagle eyed marcher spots Bruce Kent (third from right) as we cross underneath.
And on we march, under the next bridge, which I think might have been the New Hungerford. We've been marching for several hours now and are about a quarter of the way round, there is no let up to the crowds who range as far as the eye can see, behind and in front of us.
And at last something we all recognise, the London Eye comes into view
Young people "having a ball" on the Embankment as we draw close to the 3rd hour on the march. Catch a glimpse of Walthamstow Labour Party banner being carried along behind.
It's about this time that I bump into James Anthony, marching with his UNISON group, and then catch sight of Annie Key's children's banner in the distance, having admired it on FB on the coach on the way in.
We walk along Whitehall, pausing to boo loudly outside Downing Street. Chants ring out of "What do we want? Regime change! When do we want it? Now!" It takes an hour to make it this short distance and we reach Trafalgar Square at 4pm. It is absolutely heaving and for a while we are unsure how to progress, there are so many people crammed into the square.
We turn into Piccadilly where we start to see the evidence of the unrest we have heard reported. The atmosphere changes a little bit, and the street is in shade, it feels chilly. People begin to hug their coats a little tighter around their shoulders. We point out paint spatters and broken window panes on several banks and shops. It's vandalism rather than violence, and it looks to be targetted at "the rich" in general, rather than any particular institutions, a jewellers has a broken window. The Ritz looks like it has been hit by a paintball gun. As we reach Fortnum and Mason the rumours tell us that there is an occupation inside, but from the outside there is absolutely nothing to see. A police van draws up to the kerb but there are no sirens.
Two enterprising and athletic people have shinned up two lamposts and are hanging a "Stop The Cuts" sign across the street.
It's half past four by this time, we have been marching since noon and we are due back on our coach at Wembley at six pm. Hyde Park is still at least another hour away and there is no indication that there will be anyone left making speeches by the time we get there, so we bail out of the march at this point and get the tube back from Green Park.
.... Back into the city centre at 10.45pm, proud to have been part of one of the biggest public demonstrations in decades.