Dry hills of ancient rock, green ranges of jungle peaks, slick summits of wet granite, fiery volcanoes of fresh ash – a great diversity characterizes the mountains of South and Southeast Asia, reflecting the variety of cultures that fill the region. Aside from the Himalayas, which we have covered in a separate chapter, South Asia comprises the Indian subcontinent and the island of Sri Lanka. It includes crystalline mountains formed of some of the oldest bedrock in the world, remnants of an ancient continent called Gondwanaland. Southeast Asia covers the Asian peninsula east of India and south of China, along with its continuation in a line of Pacific islands that curves eastward toward Australia and New Guinea. Its mountains range from the Himalayan outliers of northern Burma through the hills of Thailand and Cambodia to the volcanoes of Indonesia. The region also includes the mountainous islands of Borneo and the Philippines.