The reason for this was simple: it was erected over the traditional spot of St Kentigern's grave, and piety won the day over practicality.
The cathedral was built as a pilgrimage shrine for the relics of St Kentigern. The cult of Kentigern was expressly modelled on that of the English martyr, St Thomas à Becket, and strong corporate links were forged between the cathedrals of Glasgow and Canterbury - indeed, Glasgow even ended up with some of Becket's relics.
Relics were a key part of the attraction of visiting a medieval cathedral, as their presence was supposed to create healing miracles.
By the 15th century Glasgow Cathedral had purchased, or otherwise acquired, well over 20 significant relics, making it the leading pilgrimage destination in Scotland and nothern England.
Among its alleged treasures were part of Jesus' manger from the stable at Bethlehem, hair from the head of the Blessed Virgin Mary and bones of various saints. Sadly, all of these items, together with reliquaries of silver and gold decorated with precious stones, vanished after the Reformation.
Some were taken to Paris for safekeeping, where they disappeared following the French Revolution.
By 1484 Glasgow had been elevated to an archbishopbric. The move displeased the Archbishop of St Andrews ... the ancient diocese of St Andrews had been trying to take over, or limit, the power of upstart Glasgow for 300 years.
In 1545 two archbishops, one from St Andrews and one Glasgow, met at the door of the cathedral, each claiming superiority.
There ensued a punch-up and they clubbed each other with their archiepiscopal crosses.
The bishops were to be swept away by the Scottish Reformation in 1560.