Strong-Blocked , or  fort de Keragan , is a fortification located in the town of  Ploemeur  in the  Morbihan  in  France.
 
 It is built following the  Lorient headquarters  with the aim of strengthening the system of fortifications on the Atlantic coast of the  Brittany.
 
 Located on Keragan Island, a  small island  accessible only at low tide, it was built on the initiative of the Governor of Brittany  Louis-Jean-Marie de Bourbon, Duke of Penthièvre.
 
 Dimensions: 35  x 24  cm - thickness 1.8 cm
 Made and designed in France in Orléans (45)
 Wood: Hevea