Mizter T wrote:
..

The Barrier is indeed worth a visit, it's impressive even if it's
not closed.

You could also experience the Woolwich free ferry [1] and/or the
Woolwich foot tunnel [2]. The ferry offers some interesting views -
especially if you stand on the top of either of the exit stairways
on the level of the car deck.

The tunnel meanwhile is an atmospheric (and damp!) experience.
There's manned lifts at either end until 6pm (4:30pm sunday) - I
remember a burly lift operator who was most jovial but also
obviously kept an eye on the tunnel (via CCTV) and kept things
under control.

So you could go under/over one way and back the other.

I think - but I'm not certain - that there is a riverside walk all
the way from the Woolwich ferry approach to the Barrier. This
streetmap - http://tinyurl.com/jcef3 - shows the location of King
George V DLR station, though the mapping used is not new enough to
feature it.

The new satellite view (though not the map itself) on
http://maps.google.co.uk is recent enough to show the DLR's King George
V branch. If you enter Burt Road,London in the search box and zoom in a
bit on satellite view, you'll see Pontoon Dock station immediately south
of Burt Road, with Thames Barrier Park and the barrier itself south of
the station. As far as I can see, there's no access to the downstream
side of the Barrier from the north bank.
--
Richard J.
(to e-mail me, swap uk and yon in address)