Porrentruy

On 27 April 1792, French Revolutionary troops invaded Porrentruy and drove out the last prince-bishop, Joseph Sigismund von Roggenbach, ending 264 years of episcopal rule. The Tour Refous is a massive 13th-century circular keep standing 32 metres high with walls 4.5 metres thick. The prince-bishops had ruled from Porrentruy since 1527/1528, when the Reformation expelled them from Basel. On 17 December 1792, the Rauracian Republic was proclaimed — the first 'sister republic' of revolutionary France.

Since 2002, construction of the Transjurane highway has uncovered over 14,000 estimated dinosaur footprints in the Porrentruy district, dating to the Kimmeridgian stage approximately 152 million years ago, when the region was a shallow tropical lagoon. Both sauropod and theropod (likely Allosaurus-type) tracks have been found, with some prints over 1 metre in diameter. The JURASSICA Dinotec in Porrentruy displays over 100 tracks. The Jura Mountains gave their name to the Jurassic period.

The Porte de France is Porrentruy's sole surviving medieval city gate, rebuilt in 1563 and refurbished in 1744, with two round towers and a belfry. It points toward France, just 10 km north. In 1793, after the Rauracian Republic was absorbed by France, Porrentruy became capital of the Département du Mont-Terrible. The Congress of Vienna (1815) assigned the territory to the Canton of Bern despite the region being French-speaking and Catholic — planting the seeds of the Jura separatist movement.

Damassine is an eau-de-vie distilled from the damasson rouge, a small wild plum said to have been brought from Damascus by Crusaders. It takes nearly 900 plums to produce a single litre of brandy. The fruit falls naturally and is collected daily by hand. Damassine received AOP status in 2010 — the first for a Jura spirit. It cannot be marketed before Saint-Martin's Day (11 November). The Feast of Saint Martin is an ancestral harvest festival in the Ajoie celebrated on the second weekend of November.

On 9 December 1842, prefect Joseph Choffat launched a watchmaking initiative for the Ajoie, establishing the first apprenticeship workshop in Porrentruy Castle's hospice, training poor and orphaned children. The workshop produced 32 trained apprentices by 1850. By 1866 there were 57 watchmaking workshops in Porrentruy; by 1871, 120. A formal watchmaking school opened in 1884. Notable manufacturers included Emile Juillard (brands Bulla and Carpe Diem), Phénix, and Hélios.

The Jardin botanique de Porrentruy dates from around 1800 and is one of the oldest botanical gardens in Switzerland. Located in the former Jesuit monastery grounds (college founded by Blarer von Wartensee in 1591), it features over 80 varieties of roses, 180 varieties of iris, a Jurassian Garden with 800 indigenous plant species, and tropical greenhouses. On 1 January 1979, the Canton of Jura joined the Swiss Confederation as its 26th canton, after the referendum of 23 June 1974.

The Feast of Saint Martin is celebrated across the Ajoie on the second weekend of November. The highlight is the bouchoyade: traditional public preparation of a pig yielding dishes including bouillon, fromage de tête, blood sausage, cotines, roast pork with rösti, and totche (a sour cream tart) for dessert. The totche is considered the representative pastry of the Jura. A market in Porrentruy with over 55 vendors accompanies both weekends. When Saint-Martin falls on a Sunday, the next Monday is a local holiday.

The Tour Refous is a massive 13th-century circular keep, 32 metres high with 12-metre diameter and 4.5-metre-thick walls. Its design recalls Savoy dynasty keeps. The castle has belonged to the Bishopric of Basel since 1271. Prince-Bishop Jakob Christoph Blarer von Wartensee (1575-1608) transformed it with architect Nicolas Frick around 1588, founded a Jesuit college in 1591, and led the Counter-Reformation. On 1 January 1979, the Canton of Jura became Switzerland's 26th canton. The canton celebrates its independence day on 23 June.