A very interesting article on the new discoveries at one of Rome's biggest catacomb complex, which was thought to be a Christian site for years. The latest foundings revealed the skeletons of more than 100 humans which predate Christianity and possibly "pagan burials". Puzzled scientists are working at the site for further details and clues. From the Archaeology Magazine.

Why are Christians always so surprised when they take something or claim something for their own use that the site may have been used previously by a people who were non-Christian. As far as religion goes Christianity is fairly new.

In fact, many churches were build on sites which were previously sacred pagan sites. It was a good way to attract people who were used to gather there anyway, and at the same time make sure that they would no longer be able to worship the old way.
As a result, many early churches were riddles with pagan symbols placed there by the craftsmen so that people could continue paying their respects.

And many not so early churches...