A greeter is a person who volunteers to share his/her knoledge of his city or region to visitors.
They aren’t professionnal guides but more like a newly met friend that show you around a place that is important in their life.
Some of them speak English so it may ease communication if you only have notions of French. Website is in French language only; most of them will propose a visit in French.
It is a original and unique way to discover a city like Reims or explore Champagne area far from touristic places and crowd.
Conctact them using Greeters en Champagne
Stay also in a nice B&B rather than in an hotel is also a great way discover Reims and meet its inhabitants.