During the medieval era, the model for much romanesque architecture was

The answer is roman pantheon.

Explanation:

The Roman Pantheon is the most saved and persuasive working of old Rome. It is a Roman sanctuary committed to every one of the divine forces of agnostic Rome. As the block stamps in favor of the building uncover it was fabricated and devoted between A.D 118 and 125.But what was the first reason for the Roman Pantheon? "Skillet" meaning the world and "theon" - divine, shaped a joined imagery as a reverence to "every one of the Gods". The Pantheon was initially worked as an agnostic sanctuary for the everyday citizens to venerate the 7 Roman Gods - Sun, Moon, Venus, Saturn, Jupiter, Mercury, Mars.