Oldest warships still in service.

Seeing that ships today are not built to last more than 20-30 years I was curious as to who has the oldest ships in service. When I say in service, i mean not a ceremonial ship like HMS Victory or USS Constitution or  converted into a shore establishment like HMS Caroline.   I am aware of several WW2 era LST's in service around the world but I wouldn't call the warships. . Their are many ships, and some that I will have missed. Anything I miss I may put in a second article.

Aircraft Carrier

The oldest is INS Viraat formerly HMS Hermes from the Falklands war.
She was commissioned in November of 1959 for The Royal navy and after commanding the Falklands task force was sold to India in 1987. She is expected to remain in service until 2017 meaning  58 years in service.

Cruiser

The BAP Almirante Grau started out life as a light cruiser for the dutch. Construction started in 1939 but due to WW2 she was not commissioned until 1953. She was sold to Peru in 1973 and has received modernization in the late 1980's and can now launch missiles.  She is the last gun cruiser in service and Peru can boast to be one of 3 countries that operates cruisers after the US and Russia. 

Submarine

The Taiwanese submarine ROCS Hai Shih  started out life as USS Cutlass. Commissioned in 1945 she is the last WW2 submarine in service, being operated by Taiwan since 1973.


 Frigates

Whilst officially a cannon class destroyer escort the BRP Rajah Humabon is now classified as a patrol frigate by the Philippines navy. She was commissioned in 1943 as the USS Atherton. She is one of the few ships in service that can claim a submarine kill, sinking a German u-boat in 1945.

 Special Mentions

The Brazilian Monitor Parnaíba was commissioned in 1938 and heavily modernized in the late 1990's. She holds the titles as the worlds oldest warship in service. Spending all her career in the Amazon which means she is less corroded than other ships of her age. She is still actively patrolling the amazon after 76 years.

The VMF Kommuna falls into the category  or downright weird. Commisioned in 1915  for the Tzars navy she was originally design to rescue and recover submarines that were lost in shallow waters. Suviving 2 world wars she now is used as an undersea support vessel/ submarine rescue ship.