As part of the Cervantes Project digital library, we are developing an Electronic Variorum Edition (EVE) of Don Quixote de la Mancha. Multiple editors can create an EVE with our Multi Variant Editor for Documents (MVED), which allows collation of one base text against several comparison texts to identify, link and edit all existing variants among them. In this context we are investigating the use of visualizations to depict graphically variants in order to validate the accuracy of the textual transcriptions and to understand the similarities and differences among different printings and editions. Our broader goal is to enable users to analyze the collation’s results and to discover facts about the evolution of the Quixote textual history, and to provide evidence to eliminate printing and compositor’s errors and thus to produce a more correct edition closer to Cervantes’ original manuscript. This paper describes the visualization tool, and presents the initial results of its use.