  The Metric Dimension problem asks for a minimum-sized resolving set in a
given (unweighted, undirected) graph $G$. Here, a set $S \subseteq V(G)$ is
resolving if no two distinct vertices of $G$ have the same distance vector to
$S$. The complexity of Metric Dimension in graphs of bounded treewidth remained
elusive in the past years. Recently, Bonnet and Purohit [IPEC 2019] showed that
the problem is W[1]-hard under treewidth parameterization. In this work, we
strengthen their lower bound to show that Metric Dimension is NP-hard in graphs
of treewidth 24.
