Mark Twain Quote, Where does it come from?

[Dimensions]

"Twenty years from now you will be more disappointed by the things you didn't do than by the ones you did do. So throw off the bowlines. Sail away from the safe harbor. Catch the trade winds in your sails. Explore. Dream. Discover." - Mark Twain

 

Does anyone know where this quote is from? or maybe when? I'm trying to find out about origins and circumstances but Google is letting me down.

 

Thanks.

[vivalaultra]

Actually, that quote, though attributed to Twain, is not authenticated. It's origins are sketchy. No one knows for sure that he said it, although it's attributed to him.