I've made it to the midpoint! I now know the source of the cover on the Kindle edition that I am reading.
http://en.wikipedia.org/wiki/File:Pi...rt_Project.jpg
Spoiler:
The link between journeys and painting, especially this sort of journey, is very close. There was plenty to think about as I made my way through the snow-bound monastic orchards; and it occurred to me, in the silent fields that followed, and for the hundredth time since my landing in Holland, that so far one painter had presided over every stage of this Winterreise. When no buildings were in sight, I was back in the Dark Ages. But the moment a farmhouse or a village impinged, I was in the world of Peter Brueghel. The white flakes falling beside the Waal—or the Rhine or the Neckar or the Danube—and the zigzag gables and the muffled roofs, were all his. The icicles, too, and the trampled snow, the logs piled on the sledges and the peasants stooped double under loads of faggots. When children with woollen hoods and satchels burst out of a village school with a sudden scamper of miniature clogs, I knew in advance that in a moment they would be flapping their arms and blowing on mittened fingers and clearing a space to beat a top in, or galloping down a lane to slide on the nearest brook, with everyone—children, grown-ups, cattle and dogs—moving about in the wake of their own cloudy breath. When the wintry light crept dimly from slits close to the horizon or an orange sun was setting through the branches of a frozen osier-bed, the identity was complete.