C31 or C-31 may refer to:
Vehicles
*
Fokker C-31A Troopship, a Dutch military transport
* , a C-class submarine of the Royal Navy
*
Nissan Laurel C31, a Japanese sedan
*
Sauber C31, a Swiss Formula One car
Other uses
*
Blackstripe corydoras, a tropical freshwater fish
*
C-31 highway (Spain)
C-31 or Eix Costaner is one of Catalonia's primary highways. It is the result of merging several sections of previously existing roads, '' autopistas'' and '' autovías'' after the 2004's renaming of primary highways managed by the Generalitat de ...
, in Catalonia
*
C31 road (Namibia)
*
Bill C-31, various legislation of the Parliament of Canada
*
Caldwell 31, an emission/reflection nebula
*
Channel 31 (disambiguation) Channel 31 refers to several television stations:
Australia
The colloquial name for certain community television stations in Australia
* Access 31
* Hitchhike TV, formerly 31 Digital
* C31 Melbourne
* Channel 31 (Sydney)
* Channel 44 (Adelaide) ...
*
King's Gambit, Falkbeer Countergambit, a chess opening
* C31, a
London Cycleway
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