HER entry
Along with all Jersey's other coastal towers and historic fortifications it is a listed building, described as follows in the Jersey Heritage Historic Environment Record website:
Martello-type tower, 1808. The tower is significant as an integral part of a group of surviving Martello-type towers in Jersey that illustrates the changing political and strategic military history of the Island in the early 19th century.
A variant of the Martello, designed by Royal Engineers in England, was adopted in Jersey. Three small towers were constructed between 1808-1811 on islets off the south coast at Portelet, Noirmont and Icho. More towers were planned for the coasts around St Helier, but were not built.
Portelet Tower, also known as La Tour Janvrin, was built on Ile au Guerdain in 1808. In common with other Martello-type towers, Portelet was designed primarily for mounting artillery on the roof platform (an 18-pounder traversing gun). It has a characteristic Martello profile - squat and robust with a battered outer wall of dressed granite. There are no loopholes and very few other openings, the very thick walls themselves providing the main defence.
The first floor door faces landward and has a specially profiled threshold to enable the original entrance ladder to be withdrawn from above. Inside there is a bombproof vault designed to protect the accommodation for gunners and the small garrison on the main floor.
The islet is known as Janvrin's Tomb. It is so named after Philippe Janvrin, captain of the Esther, who on returning from Nantes in 1721 was forced to quarantine the ship and crew in Belcroute Bay, as plague had reached epidemic in France. Janvrin died onboard ship but his body could not be brought ashore because of the plague, and the court ordered that he should be buried on the islet. He was later reinterred at St Brelade's Church.
1920
1890
1875
