We deliberated for a while day on whether to go ahead with the tour as the low cloud and slight rainy conditions meant visibility would be a little obscured. We are glad we ent ahead though ! The tour guide was first class, non-stop commentary on things to look for, pointing out small details on the shores, bits of history and something for my daughters, the latest who's living where star accommodation spotting ! The Circle Line boats are clean, quiet, spacious affording good viewing on all decks. We didn't pay the extra for the premium seating, in hindsight we might have done - it was that good. Top recommendation - get there min 30 mins pre sailing - get the best seats. Top tip2 - get your drinks in quickly as the queues rise steadily and service, whilst service overall is good, I did find it a little slow. No hesitation is recommending this cruise for any visitor - and I'm known to be a critical customer ! Well done Circle Line !!