Also known as the blockhaus des Escardines, this small bunker site – one of dozens lining the coast between Calais and Dunkirk - is built around two machine gun and a mortar position as a defence for the area.
The guns were positioned inside R630 type casemates – large buildings which seem to be overbuilt for the size of guns housed within them. You can find one on the beach and one inland, although the one in the dunes is largely overgrown now. There’s also a defensive Tobruk and a small shelter still visible on the beach too.
Stp Martha’s crown jewels though are a R120a type observation post and a R633 mortar bunker, although the latter is heavily overgrown and difficult to access now.
Both have their armoured cupolas still in place – a rare occurrence as many of these were removed for their scrap metal value following the end of the war.
Inside the R120a observation bunker you can still see the rotating periscope inside the cupola - including the cogs which turned the periscope - but the bunker itself is difficult to access due to deposited sand inside the rooms.
This six-room R633 featured an armoured M19 automatic mortar turret which could rapid fire 5cm mortar bombs to cover the position from attack.
The electrically or manually operated turret could fire up to 120 mortars per minute via clips loaded with six bombs and caused a devastating amount of damage up to 750m away from the bunker.
Fewer than one hundred R633 bunkers were built, making this one of the rarest types on the Atlantikwall.