Located near the Mayenne river after which it is named in the northwest of France, Mayenne is an old town with a great many fascinating things to discover. It also forms a central point from which, after renting a car from Mayenne you can explore nearby scenic places such as Laval, Chateau-Gontier and Sainte-Suzanne which all lie just on the outskirts of the town. The area is a great example of rural France, and by obtaining car hire from Mayenne to visit these places you can experience a side of France that you wouldn't get visiting the bigger cities.
Renting a car from Mayenne means that you can head over to see the Armorican Massif which is a spectacular, naturally occurring geological fault. It is certainly worth driving over to and marvelling at. Elsewhere, outside of Mayenne, the small towns of Sainte-Suzanne and Chateau-Gontier will give you a wonderful taste of rural life in France and are the perfect places to spend a day or two sampling local delights.
One place that should definitely be visited is Laval in the overall department of Mayenne; another old historical town that's home to a fantastic castle which will delight history buffs.