Around here you'll hear people tell about going up to Portland or up to Augusta. Huh? Since when does going up mean going south? Well here in "Downeast" Maine we still think in terms of traveling by sea instead of by car. In the early days when roads were few, bridges even fewer and what was, was rough - it was easier to travel by boat from the various islands, pennisulas and towns along the coast of Maine. The prevailing winds blow up from Boston so to get to Bar Harbor one would be sailing downwind and east.
Downeast Magazine (which is a wonderful publication about the state of Maine) defines it well:
"When ships sailed from Boston to ports in Maine (which were to the east of Boston), the wind was at their backs, so they were sailing downwind, hence the term 'Down East.' And it follows that when they returned to Boston they were sailing upwind; many Mainers still speak of going 'up to Boston,' despite the fact that the city lies approximately 50 miles to the south of Maine’s southern border."