Italian Renaissance architects based their theories and practices on Classical Roman examples. The Renaissance revival of Classical Rome was as important in architecture as it was in literature. A pilgrimage to Rome to study the ancient buildings and ruins, especially the Colosseum and Pantheon, was considered essential to an architect´s training. Classical orders and architectural elements such as columns, pilasters, pediments, entablatures, arches, and domes form the vocabulary of Renaissance buildings. Vitruvius´s writings on architecture also influenced the Renaissance definition of beauty in architecture. As in the Classical world, Renaissance architecture is characterized by harmonious form, mathematical proportion, and a unit of measurement based on the human scale.
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