Stp31 at Courseulles-sur-Mer is at the heart of the Juno landing beach area and was captured by Canadian forces on D-Day.
The strongpoint runs from the fishing port town west along the beach towards Graye-sur-Mer and there's a lot to see still, including the site of the Juno Beach Centre - a superb museum dedicated to the Canadian liberators and their memory.

At the most western end of the position you can get up close to a Churchill AVRE tank. Known as One Charlie, this armoured vehicle is from the 26 Assault Squadron Royal Engineers 7th Canadian Infantry Brigade and landed on Juno beach at Graye-sur-Mer, Normandy on D-Day.
This vehicle is equipped with a front facing machine gun and a bunker busting 290mm Petard spigot mortar designed to smash through thick concrete with its 40lb, high-explosive rounds.
Unfortunately, it was stopped on the beach by a massive bomb crater not long after leaving its landing craft and the crew were forced to escape the stricken vehicle. Four of the crew were killed and two injured in the process.
The tank remained buried on the beach for over 30 years until it was recovered, restored, and placed on display. Today it stands proudly just metres from where it fell to rest, as a memorial to all those who landed on Juno Beach.
In accordance with his last wishes, the ashes of Bill Dunn, driver of One Charlie, were scattered next to the tank on November 8, 2014.

In between the beach front an the bend of the Seulles river you'll find a series of bunkers including the first of the large gun casemates at the position, a R623 machine gun bunker which covered the long stretch of beach to the west.

To the east of this, near to the sailing club, is a R612 casemate an open emplacement, and Bf69 mortar Tobruk. The R612 is known as 'Cozy's Bunker' after the Canadian soldier Lt WF 'Cozy' Aitkin and 10 Platoon of B Company The Royal Winnipeg Rifles who took the position out, neutralising the 75mm gun inside.

In front of the Juno Beach Centre museum are a number of bunkers which can be accessed via a tour led by museum staff. The largest - at the front of the site - is one of the rarest bunkers on the the Atlantikwall - a R666 observation post which once sported a small armoured cupola on top, relaying information back to the chart room below. This casemate - one of only eight ever built - also has a defensive Tobruk as part of its structure. Behind this is a large 'Kommandostand', a multiroom group shelter and ammunition storage area which was one of the earliest builds at the site and features a mix of materials including concrete, blocks, and local bricks.
Both the R666 and the Kommandostand can only be accessed as part of the guided tour from the museum, which is highly recommended.

Along the from heading east are a number of smaller Tobruks and a 1694 Ringstand which are largely buried under the dune vegetation now and a Doppelschartenstand - a double embrasure casemate for a 5cm KwK anti-tank gun which covered the point of the mouth of the Seulles river leading to the port at Courseulles.