You can get this Achievement on the MMO Map or GoatZ but is much easier to obtain on MMO.
To get the achievement on the MMO Map make your way to the village which is past the fields and through the wooden bridge. Once in the Village go between a gap in the buildings off to the right and you will see the wooden boat, simply hop in and the Achievement will unlock.
For the Goatz Map head to the Whiplash area and the Boat is behind this along the docks.
Achievement is at 8:42