Caspar Van Wittel established all his life in the city of Rome, and painted its landscapes quite a bit.
This is a very good documentations for all historians too, as he documented the 'Urbs Aeterna' (Eternal City) at its best, in very varied images, even if a little serial work like Giovanni Paolo Panini was done, painting was still a work, after all.
Canaletto who was in Rome a few times from 1716 to 1720 could have seen some of his work, van Wittel was very likely the most traditional (since 1680) landscape painter in Rome, and their style didn't differ much, in comparison to other Dutch landscape painters of the time.
Caspar Van Wittel seems to have painted quite little after 1724 when his eyesight deteriorated ...