  We present a four-flavour lattice calculation of the leading-order hadronic
vacuum polarisation contribution to the anomalous magnetic moment of the muon,
$a_\mathrm{\mu}^{\rm hvp}$, arising from quark-connected Feynman graphs. It is
based on ensembles featuring $N_f=2+1+1$ dynamical twisted mass fermions
generated by the European Twisted Mass Collaboration (ETMC). Several light
quark masses are used in order to yield a controlled extrapolation to the
physical pion mass. We employ three lattice spacings to examine lattice
artefacts and several different volumes to check for finite-size effects.
Incorporating the complete first two generations of quarks allows for a direct
comparison with phenomenological determinations of $a_\mathrm{\mu}^{\rm hvp}$.
Our final result including an estimate of the systematic uncertainty
$$a_{\mathrm{\mu}}^{\rm hvp} = 6.74(21)(18) \cdot 10^{-8}$$ shows a good
overall agreement with these computations.
