  We analyse the large-scale structure out to 100 Mpc around a sample of 16
confirmed fossil systems using spectroscopic information from the Sloan Digital
Sky Survey Data Release 16. We compute the distance between our FGs and the
centres of filaments and nodes presented in \citet{Chen2016}. We also study the
density of bright galaxies, since they are thought to be good mass tracers, and
the projected over densities of galaxies. Finally, we apply a FoF algorithm to
detect virialised structures around our FGs, in order to have an estimate of
the mass available in their surroundings. FGs are mainly found close to
filaments, with a mean distance of $3.7 \pm 1.1$ R$_{200}$ and a minimum
distance of 0.05 $R_{200}$. On the other hand, none of our FGs is found close
to intersections, with a mean and minimum distance of $19.3 \pm 3.6$ and 6.1
$R_{200}$, respectively. There is a correlation for which FGs at higher
redshifts are found in denser regions, when we use bright galaxies as tracers
of the mass. At the same time, FGs with the largest magnitude gaps ($\Delta
m_{12}$ > 2.5) are found in less dense environments and hosting, on average,
smaller central galaxies. Our results suggest that FGs formed in a peculiar
position of the cosmic web, close to filaments and far from nodes, in which
their interaction with the cosmic web itself can be limited. We deduce that FGs
with faint BCGs, large $\Delta m_{12}$, and low redshifts could be systems at
the very last stage of their evolution. Moreover, we confirm theoretical
predictions that systems with the largest magnitude gap are not massive.
