Recent measurements of the production of single top quarks in proton--proton collisions at centre-of-mass energies of $\sqrt{s}=7\,$TeV, $8\,$TeV and $13\,$TeV with the ATLAS detector at the LHC are presented.
Four measurements of the production cross sections for single top quarks via the $s$- and $t$-channel exchange of a $W\,$boson as well as in association with a $W\,$boson are discussed.
The results are compared to state-of-the-art theoretical calculations, and used to extract the value of the CKM matrix element $V_{tb}$.
Recently found evidence for the production of single top quarks in the $s$-channel at $8\,$TeV is presented.
Finally, the determination of anomalous couplings at the $W-t-b$ vertex from an analysis of top-quark decays is shown.