"Where's the University?" That is one of the most common questions of visitors to Oxford, particularly North American visitors who may expect a carefully laid out campus like those they see at home. But Oxford University is not a homogenous whole, rather it is a collection of independently founded colleges, each with its own history and its own administration.
Going back to the origins of Oxford University, there were no buildings at all. The "university" really consisted of students gathered about individual Masters (teachers). These students lived in academic halls, or sometimes, in the house of the Master.
Many of the older colleges were regional in nature. Jesus College drew its students from Wales, Queen's College from Cumberland and Westmorland, and so on.
Another point to remember about the older colleges is that they were religious foundations, not simply academic. St. John's College was founded to educate Cistercian monks, New College to supply clergy to replace those who had died in the Black Plague.
The founding date of the university presents equal problems. Although the University has claimed an association with Alfred the Great, this seems quite unlikely. The oldest colleges are Merton, Balliol, and University College, dating back to the mid-13th century.