There are now some 160 million people living on Java, the most populated of the many islands that make up Indonesia. It is about 1,000 km (620 miles) long, with a spine of volcanic mountains running along its length.
In the past, the mountains made connections between different parts of Java difficult to maintain, and various traditions grew up in separate parts of the island. The local veneration of ancestors continued in some parts, but the monument called Borobudur (or Barabudur) has no part in that tradition. It is Indonesia’s largest religious monument and it is dedicated to Buddhism.