Complex sentence: Nevertheless, those buildings that did survive seem to hold on tenaciously to traditions of Visigothic architecture with few, if any, Islamic features, which comprises them in the ample concept of Pre-Romanesque architecture.
Split into simpler sentences: Nevertheless, those buildings that did survive seem to hold on tenaciously to traditions of Visigothic architecture with few, if any, Islamic features. All this includes them in the ample concept of Pre-Romanesque architecture.