  We consider the intersection of N different interfaces interpolating between
different $Z_N$ vacua of an SU(N) gauge theory using the Polyakov loop order
parameter. Topological arguments show that at such a string-like junction, the
order parameter should vanish, implying that the core of this string (i.e. the
junction region of all the interfaces) is in the confining phase. Using the
effective potential for the Polyakov loop proposed by Pisarski for QCD, we use
numerical minimization technique and estimate the energy per unit length of the
core of this string to be about 2.7 GeV/fm at a temperature about twice the
critical temperature. For the parameters used, the interface tension is
obtained to be about 7 GeV/fm$^2$. Lattice simulation of pure gauge theories
should be able to investigate properties of these strings. For QCD with quarks,
it has been discussed in the literature that this $Z_N$ symmetry may still be
meaningful, with quark contributions leading to explicit breaking of this $Z_N$
symmetry. With this interpretation, such {\it QGP} strings may play important
role in the evolution of the quark-gluon plasma phase and in the dynamics of
quark-hadron transition.
