Train
Take the train Ter at the station Cognac .1
The journey takes approximately 1 h 21 min. Ticket price is about 13–35 EUR. The travel distance is 100 km.
Carrier is SNCF.
Get off at the La Rochelle Ville
Drive
In a rental car
The drive will take 1 h 14 min.. The distance between Cognac and La Rochelle is 104 km. You will use 8 liters of gasoline at a cost of €10.4.
See on this site which rental company has the best deal.