Château-Gontier is a former commune in the Mayenne department in north-western France. On 1 January 2019, it was merged into the new commune Château-Gontier-sur-Mayenne. It is about 30 km south of Laval, the préfecture of the department of Mayenne. Château-Gontier is home to the Refuge de l'Arche, also known as the Ark Refuge, a refuge for ab…Château-Gontier is a former commune in the Mayenne department in north-western France. On 1 January 2019, it was merged into the new commune Château-Gontier-sur-Mayenne. It is about 30 km south of Laval, the préfecture of the department of Mayenne. Château-Gontier is home to the Refuge de l'Arche, also known as the Ark Refuge, a refuge for abandoned or mistreated animals.