Look for Longer: How many London Underground stations can you find?

Last week I received an email from an unnamed agency who offered to send me a sneak peek over an upcoming project called Look for Longer (#lookforlonger). I have been promised that it would be a mind boggling cryptic challenge aimed at testing Londoner's knowledge of the city. When you combine by love for London and fun, it's difficult to say no.

The package arrived a couple of days ago and it was nothing like I expected. It was a beautifully drawn medium sized poster, which I will be framing, and the biggest magnifying glass I've ever held. The poster contains puns in references to London Underground, Docklands Light Railway and Overground stations such as Angel, Elephant & Castle, Bond Street, Knightsbridge, King's Cross, Swiss Cottage, Marble Arch, Seven Sisters and many more. How many tube stations are referenced in this poster I do not know (update: 75), but I bet there are plenty more to be found. If you love London and are into a bit of fun, you will enjoy poking through this poster with said magnifying glass.

As to what this campaign is aimed at, I am totally in the dark myself. Stay tuned on 3 October when the campaign is officially unveiled.

Update: The campaign has been launched and it is a both a game and competition courtesy of CBS Outdoor. Brilliant stuff. Do check it out!

As of last week, I've found all 75/75 stations, plus a red herring. ;)

Update: I don't actually condone checking out all the solutions posted by various commentators below, but if you are really stuck, do ask!