If you need to ask this question then may I suggest that travel to Australia is not for you until you have read a few more books.
There were not any castles in the roman times as they did not make any
Any castles in Australia are, of course, of very recent date, were never used as fortifications, and have been built purely as tourist attractions. Their popularity varies from year to year.
The Roman did not have any castles. Castles emerged after the end of Roman civilisation, during the Middle Ages.
lots
yes there is
it was wrecked before any other castles in the UK were... i think!
Yes. Swedish Wikipedia has 228 articles on Swedish castles ("slott" in Swedish)
There Was Castles Before 1066 But They Were Not Recorded So Therefore No - One Knows About Them, But There Definitely Was Castles Before Then, Hope This Helps xx
Yes, Holland has at least 85 castles, in addition to others that have been lost to time.
There are no genuine medieval castles in the USA, because the Americas were not discovered until after the medieval period had ended. There are the "fairytale" Disney castles and some modern attempts at reconstructing medieval castles, but no genuine ones.
yes
Yes, many.