Grenoble is well connected by rail and reasonably served by air, though most international visitors fly into Lyon or Geneva and transfer.
By train. The TGV connects Grenoble to Paris Gare de Lyon in about three hours via Lyon Part-Dieu. Regional TER trains run frequently to Lyon (1.5 hours), Chambéry, and Valence. The train station (Gare de Grenoble) is centrally located, a short tram ride from the old town.
By air. Grenoble-Isère Airport (GNB) is about 50 km northwest of the city, mainly used by seasonal ski-charter flights. It is small and only open during limited hours. A bus runs into town, or you can take a taxi (around 70 euros, 35–45 minutes). Lyon-Saint Exupéry Airport, about 100 km away, has far more flights and a direct bus connection to Grenoble. Geneva Airport (180 km) is another option — about two hours by car, though cross-border train connections are slow.
By car. Grenoble sits at the junction of the A48 (from Lyon), A41 (from Chambéry/Geneva), and A51 (from Gap/the south). Driving from Lyon takes about an hour, from Geneva about 90 minutes.