The Old Improbable Island Wiki

A highly popular game, with fans in most age groups.¹⁾ To play, all you need is a map of the London Underground. For beginners, the Ancient & Modern is recommended, which allows no moves out of Jessop's Loop. Here are some tips:

• Boxing out the F, J, O and W placings draws the partner into an elliptical progression north to south
• In weak positional play, it is vital to consolidate an already strong outer square, e.g., Pentonville Road
• In a straight rules game, it's inadmissible to transfer inversely, which is otherwise a powerful tactic
• Opening the triangle will block any of the three possible reverse draws and is usually played early in the game (before the Central Line has been quartered) so that the risk of a diagonal move is negligible, as is the possibility of quartering
• The lateral shift decisively breaks opponents' horizontal and vertical approaches.
• The A40 northbound used as a counter-play offers rear access to suburban bidding