A proper metric space $X=(X,d)$ is called {\em antipodal} if -- with $[x,y]=\{z\in X\,\colon\,d(x,y)=d(x,z)+d(z,y)\}$ -- for every $x\in X$ there exists some $y\in X$ such that $[x,y]=X$. A connected undirected finite graph~$G$ is called {\em antipodal} if its associated graph metric is antipodal.
Here we characterize antipodal graphs of diameter~$3$ and
show that almost every graph is an induced subgraph
of some antipodal graph of diameter~$3$.
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