John Grundy has been searching high and low to bring us the lowdown on high streets, in this week's Grundy's Wonders. Whether it's called Main Street, Broad Street, Front Street or even just plain High Street, the main shopping street is the most important part of any town.John's journey through the North East, from Northumberland to North Yorkshire, starts in his own local High Street at Gosforth in Newcastle. While Gosforth certainly has its fair share of shops, it's not quite up to the mark. That's despite the fact that the area was John's favourite suburb in the first programme of this entertaining series.At Alnwick and nearby Warkworth in Northumberland, John's fascinating history lesson explains how burgage plots became burger bars and how ancient laws, which divided up High Streets, decided the shape of shops to come. Barnard Castle is a brilliant example too of how the size of elegant town houses dictated the look of the main shopping street. The County Durham market town has examples of shops from almost every era.Stokesley in North Yorkshire is also a contender for this week's Grundy's Wonder award, although quite where Barbie and a fish and chip shop fit in is intriguing. As for this week's victim of 'Grundy's Great Boot Of History', see if you can guess which North East high street has "ghastly, megalomaniac, smash-your-face-in sort of architecture".