Grand is not next door to Epinal, but it is one of the most intriguing ancient sites in the Vosges department. The village preserves the remains of a large Roman amphitheatre and a remarkable mosaic, evidence of a sanctuary town that was once far more important than its present size suggests.
It makes sense as a day trip for travellers with a car and an interest in Roman Gaul. Combine it with small villages of the western Vosges rather than treating it as a quick city sight.