Nice map and interactive display of some of the major submarine cables providing internet and telephony services to the world. The technology is pretty amazing.
From TeleGeography comes this map from 2014. These maps are too large to embed - just visit the links.
Here is the page that links to the interactive map: Submarine Cable Map
I know a couple ex-Military cables that are being used for scientific research that are not on this map. These maps may outline the territory but they do not fully represent the landscape...
I am reminded of Neal Stephenson's wonderful essay in Wired from 1996 - Mother Earth Mother Board
Close to twenty years old but still spot on. Submarine cables have always been like the SR-71 Blackbirds of their day - engineered and constructed 30 years ahead of the state of the art.