The Robinson dry dock was completed in 1870. It is situated in the Alfred Basin of Table Bay Harbour, Cape Town, South Africa.
Enigma is currently in the Robinson dry dock.
Update: Enigma XK was out of dry dock this morning. She has been in Cape Town since March 2015 and an officer told me this morninh that she can be chartered to Antarctica. That is, if your wallet is as deep as the South Atlantic.
Also,the synchrolift which is another type of ingenious dry dock.
The caisson that seals the dry dock.