Defence Minister Rajnath Singh on Monday visited Siachen, the world’s highest battlefield, and reviewed India’s overall military preparedness in the region.Singh’s visit to Siachen came over a week after the Indian Army marked the 40th year of its presence in the strategically key region. He said Siachen is  India’s Sacred Land Of Valour and Courage.  The defence minister, accompanied by Army Chief Gen Manoj Pande, reviewed the overall security situation in the region.