The Notre-Dame-de-Nazareth cathedral, built in the 11th century, is a majestic stone building on its own, and has the added feature of a very lovely Cloister walled in at the side.
This cathedral is located to the west of the town center, where the main road bridge crosses the river (not the Roman bridge). There's a parking lot beside the cathedral, a bit smaller, shadier and less hectic that the main parking lot in the center, and it's only a five-minute walk into town from here.
This cathedral of Notre-Dame-de-Nazareth shouldn't be confused with Vaison-la-Romaine's other cathedral, Saint Quenin, located up in the Medieval section of the Haute Ville, and called the cathédrale de la ville haute.
Notre-Dame-de-Nazareth was constructed on a much earlier paleochristian site, and was the Medieval town's principal church only until the second half of the 12th century. With serious conflict between the "church" and the Counts of Toulouse, the Counts built a castle on top of the hill on the left bank of the river (the current Haute Ville). Raiders and pillagers were making life difficult along the valley, and the population moved from the valley up to the rock around the base of the castle for protection, and the Notre-Dame-de-Nazareth cathedral fell in to disuse for a few centuries.
By the 19th century the valley was again populated, and Notre-Dame-de-Nazareth became the town's parish church in 1897.
The Cloister has arcades on all four sides, surrounding a small garden. A side door allows entry directly into the cloister, but during our last trip to Vaison-la-Romaine, the cloister could be entered only through the cathedral.