  We establish fractional Hardy inequality on bounded domains in
$\mathbb{R}^{d}$ with inverse of distance function from smooth boundary of
codimension $k$, where $k=2, \dots,d$, as weight function. The case $sp=k$ is
the critical case, where optimal logarithmic corrections are required. All the
other cases of $sp<k$ and $sp>k$ are also addressed.
