At the time, all of what we think of as the sea between Borneo, Sumatra, and Java, and on up to Thailand and Taiwan, and the whole South China and Yellow Seas up to Korea was all dry land, like a million square miles of it.

Borneo was high ground. Most of what was going on with humanity at the time, according to cave painting evidence, was there and is now almost all under water.

There is a hill on Java built over 20,000 years ago. Excavation was halted, by the Indonesian government, for reasons not expressed.