I know that Chinese traders ranged far and wide around the Indian Ocean and western Pacific, but how much of the world beyond that did they know about? For example, did they have any information on the existence of Australia before European explorers made it there? What about Europe before the Mongols brought back information on it from their conquests in Russia and eastern Europe?
This is the oldest surviving Chinese world map, painted on silk in 1389. Frankly anything further south of Hainan or west of Xinjiang becomes really hazy. If you're interested in the actual trade and knowledge of routes and travel, I suggest reading this. It's an Arabic travelogue on visiting India and China during the 10th century. I read it a while ago so my knowledge is a bit fuzzy, but the Arab as well as Chinese traders seemed to have had a rudimentary working knowledge of how to get from Iran to China or the other way around at least by using a sea route. Not sure about Australia. Here's an interview relating to the new translation.
We know that the Chinese definitely knew about the existence of Europe, and in the Ming Dynasty the emperor sent out Zheng He who explored SE Asia, India, and Eastern Africa. In these voyages he took gifts and brought tribute back to China including a giraffe. The Map you want to see is probably the Mao Kun map from Ming military document called the Wubei Zhi. Hope that helps.
Not a map, but there's a third century account called the [Weilüe] (https://depts.washington.edu/silkroad/texts/weilue/weilue.html) that describes Parthia, India and the Roman Empire
