We present results from a comprehensive study of the location of the chiral critical surface, which separates regions of
first-order chiral transitions from analytic crossovers, in the bare parameter space of lattice QCD with unimproved
staggered fermions. We study the theories with $N_f\in[2,8]$ and trace the
chiral critical surface along diminishing lattice spacing, with $N_\tau=\{4,6,8\}$. This allows for an extrapolation to the lattice chiral limit,
where the surface has to terminate in a tricritical line, employing known tricritical scaling relations. Knowing the phase structure in
the lattice bare parameter space allows to draw conclusions for the approach to the continuum and chiral limits taken in
the appropriate order. Our data provide evidence for the continuum chiral limit to feature a second-order transition for all
$N_f\in[2,7]$. We perform an analogous scaling analysis with already published data from $N_f=3$ $O(a)$-improved Wilson
fermions, which is also consistent with a second-order transition in the continuum. A modified Columbia plot
reflecting those results is suggested.