In Romanesque churches, what architectural addition is made to accommodate large crowds of pilgrims?

The ambulatory is the correct architectural addition in Romanesque churches designed to accommodate large crowds of pilgrims. This semi-circular or polygonal passageway surrounds the apse, allowing for the movement of pilgrims and churchgoers around the altar without disturbing those who are engaged in worship. The design facilitates the flow of people, especially during religious festivals or events, when attendance was significantly higher.

In Romanesque architecture, the need to accommodate large gatherings became increasingly important. The ambulatory not only enhances the functionality of the church during busy times but also showcases the emphasis on pilgrimage in Medieval Christianity, where the faithful often traveled significant distances to visit important relics housed in these churches.

The choir loft, while useful in some church designs, does not have the same purpose of facilitating movement around the church for large numbers of people. The transept, which extends the church layout crosswise, does create more space within the building, but it does not specifically ease the flow of pilgrims around the altar. A bell tower serves a different function, primarily related to the call to worship and does not address the need for accommodating large crowds directly. Thus, the ambulatory is uniquely suited to enhance the experience and accessibility for pilgrims visiting Romanesque churches.