Advenio + ad

Latin Learning Latin
1

I am going through LLPSI, and something struck me as odd in Chapter 7. The book introduces advenio in the following sentence:

Ecce Iulius ad villam advenit.

If advenio is ad + venio, why is the additional ad before villam used?

2

Repetition of the preposition (!) from the compound prefix is common in Latin. Here, in the same way you wouldn’t in English say “Look, Julius arrives his villa” but “Julius arrives at his villa” so Latin normally uses ad.

3

Thank you!