I'd have guessed that goods from Sri Lanka got to Rome via the Red Sea?

My recollection of an "Empire" podcast episode I listened to recently (warmly recommended!) is that as much as half of all Rome's tax was raised at Egyptian ports on goods coming up the Red Sea.

yes that might be a shorter path than overland. it would be my guess that in time deeper than roman, egyptian cash and goods were attractive to people in distant lands. Without going full Thor Heyerdal "Ra" they would have been capable of sailing coastal routes round if not a more direct route across the Arabian Seas

But it's equally likely they traded indirectly with any of the coastal economies around the Gulf, and Horn of Africa.

A major trade route also was from Constantinople up the black sea and then the dnipro river up to the Baltic.

Yes, via Berenice Troglodytica

>as much as half of all Rome's tax was raised at Egyptian ports

Interesting and makes sense to me. I remember reading a long time ago, when the Eastern Empire lost Egypt to the Arabs, it was considered a huge major disaster for them.

Yes, India and the Romans had extensive trade relations for the 6 centuries between the Romans conquered Egypt until the Arabs took it.

Facts: https://en.wikipedia.org/wiki/Indo-Roman_trade_relations

As I understand it, the Silk Road only became important when the sea route was closed. It lost its importance 800 years later when the Portugese found the sea route around Africa.

Oh there were a good number of romans who had been to india and sri lanka, there were even a good number of roman traders from egypt who sailed as far as malaysia which they called the Golden Chersonese. They didnt really know about china but had some vague ideas that a large empire existed in the east names sinae but iirc they did send a diplomatic mission to it which ended up in vietnam being robbed if I remember right before ending up before the han dynasty with very little tribute and generally being a bit of a dissapointment. There were several other merchants and diplomatic missions over the years but in general it was of minor importance to both empires, far outside their spheres.

Don't forget there was also security collaboration between the two great Empires:

https://en.wikipedia.org/wiki/Dragon_Blade_(film)

And sometimes war:

https://en.wikipedia.org/wiki/Asterix_%26_Obelix:_The_Middle...

I'm usually annoyed as fuck by the idiotic cries of "Wikipedia isn't a source, ha ha ha!" all over the Internet; on the contrary, WP is usually not only an adequate but actually a pretty good first source for ordinary online discussions (and then if you really want to get into details, continue from WP's footnotes).

But in this particular case, with these particular WP articles... Yeah yeah, you were probably kidding. But there are also more serious articles on the subject. Like https://en.wikipedia.org/wiki/Sino-Roman_relations .

I was kidding but thanks for the more serious link anyway.