Lincolnshire has a bit of Wolds, but really deserves its reputation as pretty flat. Perhaps Wowbagger was thinking of the towering mountain ranges of Norfolk?
I was really surprised by Lincolnshire when I rode there last year.
The flattest, easiest 60-mile ride I've ever done was from York to Brigg. As far as the Humber bridge, all in that county whose name escapes me for a moment but that's renowned for its hills, it was incredibly easy riding.
After Brigg, once you reach Caistor, with its vertical high street, you stay above 400' for the next 30 or 40 miles - I doubt if there's another road in Britain which stays so high for so long as the B1225. Not only is it hilly, it's almost totally deserted, a natural barrier keeping the northerner at bay.
Once you escape the hills, the ride from Horncastle to Boston is alongside a dead-straight canal for about 12 of its 18 miles.
After Boston, it's another 60 miles of dead flat, with headwind, until you reach Chris S's house. It's a bit like something from Tokien - the First Homely House after the North of England.