Mantes-la-Jolie carries its pretty name with a straight face, though the town of forty-four thousand is mostly practical rather than pretty, a Seine-side workhorse about fifty kilometres downstream from Paris. Tradition says Henri IV gave it the nickname, and the one thing that truly justifies it is the collegiate church of Notre-Dame, a Gothic building of the twelfth and thirteenth centuries whose façade and proportions echo the cathedral in Paris so closely that architects call it a rehearsal for it. Walk in and the light through the nave is worth five minutes even if you are in leathers.
For a rider, Mantes is the natural place to gather yourself at either end of a day. Fuel is easy, since a town this size has stations all around the ring roads, as well as supermarkets, bakeries and a station with trains to Paris Saint-Lazare if you need to bail out. Across the river lies Limay, with an old humpbacked bridge and a church on the slope, and the cluster of Mantes-la-Ville beside it. The two bridges over the Seine are bottlenecks at rush hour, so a finish here at six in the evening can cost you twenty minutes in a queue.
What makes the area good for riding is what lies on either side. North of the river the Vexin plateau rolls away in wheat and rapeseed, cut by small valleys and strung with villages of pale limestone, while downstream the Seine swings through long loops under white chalk cliffs. The roads that drop to the water tend to be narrow, with blind bends and walls, and they are at their best early on a weekday when the river mist has not yet lifted. Surface quality is generally fine, though farm traffic leaves mud on the corners at harvest and in wet weather.
If you have time at the end of the ride, sit by the Seine and watch the barges. Commercial traffic still moves grain, sand and containers along this stretch, and the slow rhythm of the water is a good way to let the engine cool and the day settle. The cobbled lanes of the old centre are worth a slow walk, with the bike parked near the church.