Travelling is the broadening of horizons in hope of betterment. In the story of American settlement this process is both physical and metaphorical. Settlers struck out in search of new horizons; visions of a landscape from which they hoped to enclose a new life. The Oregon Trail was one such journey.
Now the landscape is fenced, with the people in it, the terrain has been charted and limitless opportunity capped, but yearning remains. In a sense America has never stopped travelling west; whilst the pursuit of happiness leads toward an ever-receding goal, people wait for greener grass.