  We classify AdS$_3$ solutions preserving $\mathcal{N}=(8,0)$ supersymmetry in
ten and eleven dimensions and find the local form of each of them. These
include the AdS$_3\times$S$^6$ solution of \cite{Dibitetto:2018ftj} and the
embeddings of AdS$_3$ into AdS$_4\times$S$^7$, AdS$_5\times$S$^5$,
AdS$_7/\mathbb{Z}_k\times$S$^4$ and its IIA reduction within AdS$_7$. More
interestingly we find solutions preserving the superconformal algebras
$\mathfrak{f}_4$, $\mathfrak{su}(1,1|4)$, $\mathfrak{osp}(4^*|4)$ on certain
squashings of the 7-sphere. These solutions asymptote to AdS$_4\times$S$^7$ and
are promising candidates for holographic duals to defects in Chern-Simons
matter theories.
