The Greeks gave us perspective, architecture ( the "modern" style), a lot of the common units and measures still used today in some form or the other, and a lot of the beginnings of mathematics, philosophy and the Scientific Method. the Romans did more, but were hampered by the one thing they did not have, a positional number system, which allowed for both positive and negative numbers and, more importantly, the notion that ZERO is a valid, usable and important number. that had to be imported from the Arabian peninsula, along with base 10 mathematics, along with base 12, base 16 and base 60 and 360 maths as well.
Remember the modern space age is determined, in one dimension, by the ass end of 2 Roman war horses together in a chariot.