There are numerous castles in the Gersdépartement of France. Many are little more than ruins and some are barely discernible, while others have been converted into modern homes. Castles or their remains may be found at the following locations, among others:
Bassoues: The Château de Bassoues dates from the last quarter of the 14th century. The property of the commune, it has been listed as a monument historique since 1840. It was built by Arnaud Aubert, who became Archbishop of Auch in 1361. The accounts for the year 1370-71 of Raymond Sans, treasurer of Auch, detail the building of the castle. (43°34′46″N0°14′52″E / 43.57944°N 0.24778°E / 43.57944; 0.24778)
Bivès: Originally a 13th-century structure, the Château de Bivès was altered for Bernard de Castelbajac in the last quarter of the 16th century when the residence was altered and a tower added. Further alterations were made in the last quarter of the 19th century. It is privately owned. (43°50′6″N0°48′26″E / 43.83500°N 0.80722°E / 43.83500; 0.80722)
Cassaigne: has two castles, both privately owned. The Château de Cassaigne dates from the 13th, 15th and 18th centuries. Of note are the façades and roofs, including those of the common buildings, the moat and bridge, the 18th century dining room and its chimney and the ground floor kitchen in the north wing. The Château de Cassaigne has been listed as a monument historique since 1987. (43°54′30″N0°20′9″E / 43.90833°N 0.33583°E / 43.90833; 0.33583). The Château de Léberon was constructed in the 15th, 16th and 17th centuries and has been listed as a monument historique since 1963. (43°54′40″N0°21′7″E / 43.91111°N 0.35194°E / 43.91111; 0.35194)
Castet-Arrouy: The Château de Gachepouy was built between 1579 and 1584 for Anne d' Aydie, baroness of Pordéac. A staircase tower, now destroyed, was added in 1601 for Catherine des Fontaines, by Raymond Salles, master mason of Lavit de Lomagne. (43°59′4″N0°44′6″E / 43.98444°N 0.73500°E / 43.98444; 0.73500)
Condom: The Château de Mothes dates from the last quarter of the 13th and first quarter of the 14th centuries, with additions from the 18th and 19th centuries. It is a privately owned monument historique, so listed since 1987. (44°0′49″N0°25′28″E / 44.01361°N 0.42444°E / 44.01361; 0.42444). The Château de Pouypardin dates from the last quarter of the 13th and first quarter of the 14th centuries, with additions in the 15th and 16th centuries. A monument historique since 1986, it is particularly noted for its orangery, tower, hall, staircase and roof. (43°59′31″N0°19′45″E / 43.99194°N 0.32917°E / 43.99194; 0.32917)
Courrensan: The Château de Courrensan was built in the 13thm 15th, 16th and 18th centuries. It has been protected as a monument historique since 1979 and is noteworthy especially for its 15th-century columned chimney in a second-floor room. A ground-floor room in the 18th-century wing contains impressive wood decoration. (43°51′0″N0°14′31″E / 43.85000°N 0.24194°E / 43.85000; 0.24194)
La Sauvetat: The Château de Sérillac was originally an ancient Gascon fortress. During the Renaissance, it was converted to a country residence. Every century from the 13th to the 18th is represented in its architecture and decoration. The castle, its grounds and the remains of the chapel have been listed as a monument historique since 2002. (43°51′16″N0°32′23″E / 43.85444°N 0.53972°E / 43.85444; 0.53972)
L'Isle-Bouzon: The commune contains the remains of three castles. A 13th-century castle was founded by the Galard family. This was totally rebuilt in the 18th century. It is privately owned. The terrace and the supporting wall have been protected as a monument historique since 1995. A 12th/13th-century castle, once the property of the family of Galard de Magnasowned and now owned by the commune, has been protected since 1951. A third castle, rebuilt in the 16th century is now a ruin and in a poor state. It has also been protected since 1951.(43°55′45″N0°43′43″E / 43.92917°N 0.72861°E / 43.92917; 0.72861)
Montréal: The Château de Balarin was constructed at the end of the 13th century on the frontier of what was then English territory. It underwent substantial modification at the end of the 15th century to make it habitable, most importantly, the addition of windows and a circular tower. Now ruined, it has been a protected monument historique since 1942. (43°57′53″N0°15′2″E / 43.96472°N 0.25056°E / 43.96472; 0.25056)
Sainte-Gemme: The 13th-century castle, improved in the 16th and 17th centuries, is linked to the Gère family. With its chapel, registered as a monument historique.
Saint-Lary: The four-storeyed ruined castle dates from the 13th and 15th centuries. It is privately owned and has been listed as a monument historique since 1933.
Seissan: The Château du Garranée was originally constructed in the 11th century. It was modified in the 13th, 14th and 15th centuries. (43°30′48″N0°32′51″E / 43.51333°N 0.54750°E / 43.51333; 0.54750) A tower is all that remains of another castle, believed to be 13th century, belonging to the abbots of Faget. The ground floor had no openings other than a small bay in the southern wall. It represented the typical medieval military architecture of the region. It was already in ruins at the French Revolution.
Sempesserre: All that remains of the castle is a tower, believed to date from the second half of the 16th or first half of the 17th centuries.