An ornate religious site, this cathedral doesn't have just one architectural identity — but that's what makes it special. Originally raised in the 5th century, the cathedral's construction continued until the 18th century, likely accounting for the variety in design. The church boasts a mishmash of Roman, Gothic, Baroque and Merovingian styles that can be seen in its facades, interior and decor.

One TripAdvisor user called the architecture both inside and outside the church "quite spectacular."

You can tour this working church — which is located about a 10-minute walk north from the Cours Mirabeau — for free from 8 a.m. to noon and 2 to 6 p.m. daily. For more information, including Mass times, visit the cathedral's website.