Cable Map is an awesome website that shows known under sea cables on an interactive map (powered by Bing). It shows that there are actually many under sea cables. I mentioned a few months ago that most intercontinental data travels through undersea cables.
I should note that the locations on the map are approximate for security reasons. Because their damage could cost millions and disrupt worldwide communications only their operators and select contractors know where they actually come ashore.
The image above links to a big static version of the map just in case the site someday goes dark.