  We use multi-scale techniques to determine the extent of local inhomogeneity
and superconductivity in Ca$_{0.86}$Pr$_{0.14}$Fe$_{2}$As$_{2}$ single crystal.
The inhomogeneity is manifested as a spatial variation of praseodymium
concentration, local density of states, and superconducting order parameter. We
show that the high-$T_{c}$ superconductivity emerges from clover-like defects
associated with Pr dopants. The highest $T_{c}$ is observed in both the
tetragonal and collapsed tetragonal phases, and its filamentary nature is a
consequence of non-uniform Pr distribution that develops localized, isolated
superconducting regions within the crystals.
