Among other things, the Romans were famous for their expert engineering skills. Many of the inventions made during their era are still of immense benefit today.
For example, Roman concrete is known to be self-healing. There is evidence that they mixed volcanic ash with their cement so that when the concrete cracked and water seeped in, it reacted with the minerals inside and solidified. Such techniques are still the subject of modern PhD thesis!
This and other topics are covered in this interesting book on Ancient Engineers' Inventions: https://link.springer.com/book/10.1007/978-3-319-44476-5
From refrigeration to computers and the forerunners of the SI units, what our ancestors did is often fascinating.
From a patent perspective, whether something is novel or inventive is decided upon with reference to addition to human knowledge. However, just because pyramids exist, does not mean we as a modern civilization are able to re-create them using the same tools and technologies. The skilled person from 2000BC constructing the first mechanical computer to track time and position with stars is very different to the skilled person working in the electronics field.
How should we treat old inventions that are re-invented?