Once the second city of the empire, Glasgow is home to many industries, famous names, and objects which are now regarded as valuable and collectable. Tim Wonnacott visits a farmers market on the shores of Loch Lomond, just outside Glasgow, where locals have brought along a range of fascinating treasures. They include a piece of rare Clutha glass, a Glasgow Boys oil painting and some antique carpenter's tools with a fascinating story. Tim tests his head for heights in the roof of Glasgow's 13th-century cathedral and explores the Kelvingrove museum.