  The behavior of black holes horizon and wormholes under the Weyl conformal
transformation is investigated. First, a shorter, but more general, derivation
of the Weyl transformation of the simple prescription for detecting horizons
and wormholes given recently in the literature for spherically symmetric
spacetimes is provided. The derivation allows for a simple and intuitive way to
understand why and when horizons and wormholes might arise in the conformal
frame even if they were absent in the original frame. Then, the conformal
behavior of black holes horizon and wormholes in more general spacetimes, based
on more "sophisticated" definitions, is provided. The study shows that black
holes and wormholes might always arise in the new frame even if they were
absent in the original frame. Moreover, it is shown that some of the
definitions found in the literature might be transformed into one another under
such transformations. Worked-out examples are given.

General Relativity and Quantum Cosmology