Heading southeast from the train station towards the lake will bring you in a couple of minutes into the compact Old Town, centred on Place du Château, a shady, charmingly laid-back square with terrace cafés that is backed by the château itself, a mighty twelfth-century turreted fortress looking out over the lake. Closed for renovations throughout 1999, it’s due to reopen in 2000 with the town’s Musée Historique occupying all six floors, displaying silver, fine art, photographs, and a comprehensive collection of Nyon porcelain. Opposite the chateau at 4 Place du Château is the headquarters of Focale, one of the most important associations of Swiss photographers; their cramped bookshop is excellent, as is the gallery downstairs showing contemporary photography. The Rue du Vieux Marché leading west off the square brings you past a statue of Julius Caesar to the impressive Musée Romain on Rue Maupertuis (Tues–Sun: April–Oct 10am–noon & 2–6pm; Nov–March 2–6pm; Fr.6 ticket covers all of Nyon’s museums; SMP). The museum is housed in a Roman basilica, originally part of Nyon’s forum; a giant trompe l’oeil fresco of the original basilica’s interior on the wall outside, as well as a model in the museum, give an idea of the size of Nyon’s public buildings in its Roman heyday. The museum’s extensive collection is very well laid out, but with notes only in French – you pass first into the central area (the nave of the basilica) which houses inscriptions, statues and architectural details, and from there move around the walls of the room through zones devoted to daily life, crafts and religion.

The street ends at the small but atmospheric Église Notre-Dame, dating from 1110 and of unusual asymmetrical design, endowed with new, glowing stained glass. The arched Porte Ste Marie round the corner gives onto the Esplanade des Marronniers (chestnut trees), exposed to fresh lake breezes and dominated by two-and-a-half impressively sited Roman columns silhouetted against the blue. Walking along the city walls east and down some steps to the lakefront delivers you to the small, diverting Musée du Léman, 8 Quai Louis-Bonnard (April–Oct Tues–Sat 10am–noon & 2–5pm, Sun 10am–5pm; Nov–March Tues–Sat 2–5pm, Sun 10am–5pm; combined ticket with Musée Romain; SMP). The ground floor has informative displays on the lake fauna, with large aquariums, while up above are paintings, models of ships and disquisitions (in French) on how to protect the lake’s natural resources. From the Place de Savoie, 150 metres to the east, with its jetty from which you can make out the plume of Geneva’s Jet d’Eau some 20km away, atmospheric Rue de Rive heads slightly uphill, lined with antique shops and some very odd murals on sidewalls of cartoonish figures peeping out of painted windows. At the end, Rue de la Colombière continues uphill, and where it meets Rue de la Porcelaine you should spot Nyon’s Roman amphitheatre half hidden in the grass a little east, virtually the same size as the one at Avenches but much more ruined and unfortunately now hemmed in by modern housing developments.