for the troops. Eventually normality came back in the fall of 1917. The British army took over the defences at the western end of the ridge during the following twelve months, thus bringing relief. During the summer of 1917, the Battle of the Observatories was a series of local attacks and counterattacks to gain control of high positions commanding the views between Craonne and Laffaux. In October, after the Allied victory at the Battle of La Malmaison, the German forces left the Chemin des Dames and moved to the north of the Ailette River valley. The Third Battle of the Aisne came as a complete surprise to the Allies, including British troops who had been sent there to rest in a quiet sector. A German breakthrough was aided by orders of a French general to mass troops in the front line – a tactic by this date discredited. The penetration broke into open country and fighting went on from 27 May to 6 June 1918, but ran out of energy owing to lack of a strategic objective and lengthening supply lines. During the Second Battle of the Marne, the last fight on the Chemin des Dames occurred between 2 August and 10 October 1918. Today There are numerous war memorials and cemeteries, German, French and British, all along the chemin. Beneath the ridge is an almost square kilometre (250 acre)cave network called "The Dragon's Lair" (La Caverne du Dragon). The caverns originally were a tunnel system created from excavations of limestone for building purposes in the 17th century. The caves are some below the surface. During World War I, the caves were used by both French and German forces as field hospitals and command posts, sometimes simultaneously. The artillery bombardment of the area actually cracked some of the overlying cliffs, which can be seen today. A noteworthy visitors' centre that offers guided tours is now located at the site. In January 2020, the father-son team of Alain and Pierre Malinowski discovered the entrance to the long buried tunnel. The remains of over 270 German soldiers have been recovered to date. The route was used during Stage 6 of the 2014 Tour de France as part of the race's tribute to the men killed in the 1914–18 War. Cemeteries Approximately half of those who are buried at Chemin des Dames cemeteries could not be identified, and were interred in ossuaries or