  Differential cross-sections are measured for top-quark pair production in the
all-hadronic decay mode, using proton$-$proton collision events collected by
the ATLAS experiment in which all six decay jets are separately resolved.
Absolute and normalised single- and double-differential cross-sections are
measured at particle and parton level as a function of various kinematic
variables. Emphasis is placed on well-measured observables in fully
reconstructed final states, as well as on the study of correlations between the
top-quark pair system and additional jet radiation identified in the event. The
study is performed using data from proton$-$proton collisions at
$\sqrt{s}=13~\mbox{TeV}$ collected by the ATLAS detector at CERN's Large Hadron
Collider in 2015 and 2016, corresponding to an integrated luminosity of
$\mbox{36.1 fb}^{-1}$. The rapidities of the individual top quarks and of the
top-quark pair are well modelled by several independent event generators.
Significant mismodelling is observed in the transverse momenta of the leading
three jet emissions, while the leading top-quark transverse momentum and
top-quark pair transverse momentum are both found to be incompatible with
several theoretical predictions.
