Final answer:
The oldest H. erectus/ergaster fossils found outside of Africa are between 1.2 to 1.6 million years old, discovered on the island of Java in Indonesia.
Step-by-step explanation:
The age of the oldest fossils attributed to H. erectus/ergaster that are found outside of Africa is estimated to be between 1.2 to 1.6 million years ago. These fossils have been discovered on the island of Java, which is now part of Indonesia. Most notably, the Java Man, first found in Indonesia in 1891, is one of the oldest specimens of H. erectus found outside of Africa. The fact that H. erectus managed to migrate to an area as far as Southeast Asia is testament to their adaptability and capability to inhabit a range of environments.