  We discuss two different in general natural approaches to the ideal closure
and ideal boundary of Busemann nonpositively curved metric space. It is shown
that the identity map of the space admits surjective continuation from its
coarse ideal closure to the weak one. We consider some situations when these
closures coincide, and when they are essentially different. In particular, the
singular Minkowski space is studied as flat Busemann space, and some types of
its ideal points are described.
