It all depends on you and your wishes.
• If you don’t want to enter any buildings, you will see most of the main highlights and hear the best Ghent stories in 1.5 hour.
• If you would like to visit for example Saint Bavo’s Cathedral with the Ghent Altarpiece or Saint Nicolas Church, then a tour of 2 hours is recommended.
• If you want to dig deeper, discover the soul of Ghent and a few off the beaten track places, then 2.5 or 3 hours are well spent.