Église Saint-Nicolas is the most architecturally interesting church in Blois after the cathedral — a 12th-century former abbey church in pure transitional Romanesque-to-Gothic style. The west front is plain limestone with the double towers that mark Loire-style abbey churches; the interior is taller and more austere than the cathedral, with carved capitals and a long ambulatory around the apse.
The church is a few minutes' walk down from the château toward the Loire, on Rue Saint-Laumer. It is rarely crowded and often empty, which makes the acoustics striking — there are occasional evening concerts of medieval and Renaissance music that suit the building perfectly.