On the Square and Level

Veteran Loons will doubtlessly indulge themselves with a knowing smile on glancing at that picture of Embankment Station in the post ^above^ this one

For non-veteran Loons, however, a quick brain teaser...

What do the following have in common

• The people who built Embankment Station (a handy distance from Temple Church, Cleopatra's Needle, Grand Lodge and all sorts of other fruitiness)
  

• The people who frequent fraternal meeting places like this
  

• The people who wear hats like this

Yes, that's right, they all enjoy a good game of draughts

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