Which aspect of Romanesque architecture reflects its connection to earlier periods?

The nature of the rounded arch is a significant aspect of Romanesque architecture that highlights its connection to earlier architectural forms, particularly those used in ancient Roman structures. The rounded arch, rooted in the innovations of Roman architecture, was effectively revived and adapted during the Romanesque period to enhance the aesthetic and structural capabilities of churches and other buildings. This architectural feature not only provided strength and stability but also facilitated the construction of larger openings and the development of expansive, vaulted ceilings, which were crucial in the design of Romanesque cathedrals.

While intricate designs, high vaulted ceilings, and complex floor plans are also notable characteristics of Romanesque architecture, these features reflect more of the unique developments of the period rather than a direct continuity from earlier architectural styles. The rounded arch, in contrast, is a direct lineage from Roman engineering techniques, underscoring the influence of antiquity on this medieval architectural style. This is why the nature of the rounded arch is the most appropriate choice for illustrating the connection to earlier periods in architectural history.