Hello all

I'm in the very early stages of planning a winter/spring trip through the US, covering as much as I can, over a period of (hopefully) three/four months or so. My embryonic plan is to fly to Boston, travel New England, and head along the northern US, travelling through Chicago, Rockies etc to the West Coast, down through California, and through the southern half of the country, eventually finishing in NYC. I really want to make this a trip of a lifetime, so, if anyone has undertaken something similar, I'd appreciate any tips, must-sees, must-avoids and anything else that comes to mind.

Thanks!