Possibly readers of this journal will know that there is an official type Tube Challenge out there, that involves visiting every station on the underground (DLR excluded) in the fastest time possible.  Current record is 18 hours, 35 mins and 38 seconds. 

At only 171 stations done in one year, two months and 14 days, there's no danger of my stealing anyone's shiny trophy, however this year for Children In Need,

jamesthegill

Random bit of infrastructure:

My current favourite: Brazil-style ducts, discovered heading down the staircase at the Holloway, all steampunky loveliness.