What does "little remains aboveground from the time of the etrusacans, whose exact origin is unknown' means in the reading

The Etruscan civilization is the name given to a civilization of ancient Italy which was considered to be powerful and wealthy. It developed in the area which is currently known as Tuscany. What the author is trying to say is that it is very difficult to track the origins of this civilization, due to the fact that there are very few standing constructions that can be considered to have been built by them. The majority of them have fallen down across time or are underground.

what are local authorities doing to fix the problem

explanation:

well this is going to be a long answer lol ok so the visigoths were a branch of the goths who frequently raided rome, uh the hunas attacked the guptas a lot and weakened them, uuhm of course the romans used math and science in there every day lives i mean they had a whole empire to run, and rome was split into east and west by a general named diocletian. hope this you! : )