Troyes is one of the easier day trips from Paris, though few tourists make it. Trains run from Paris Gare de l'Est to Troyes station in around 1 hour 30 minutes on the direct service; there are also slower intercity trains that take about 2 hours. The TGV makes the journey comfortable and the frequency is reasonable throughout the day. From Troyes station it is about 15 minutes' walk to the cathedral and old town.
There is no significant airport near Troyes. Most visitors arrive by train or by car. By road, Troyes is around 150 km southeast of Paris via the A5 motorway — roughly 1.5 to 2 hours depending on traffic. Parking is available near the old town, though the streets inside the historic core are narrow.
If you are connecting from Reims, the direct journey by car takes about an hour (around 80 km via the N44 and A26). There is no fast direct train link between the two cities.