The magnificent Ghent Altarpiece, commissioned by the mayor of the city, consists of many individual panels hinged together.  Importantly, it bears the first reference to Jan van Eyck, the acknowledged "father of Northern Renaissance painting," paired with that of his brother Hubert.  Distinctive in its large scale, complex symbolism, photographic realism, and use of oil paint, this work inspired artists worldwide for centuries.  Once captured by the Nazis and hidden in a salt mine, the work has been meticulously restored.  However, art historians still debate the division of hands between the two van Eyck brothers and the fine points of its complex iconography.