  A quantum dot has been etched in bilayer graphene connected by two small
constrictions to the leads. We show that this structure does not behave like a
single quantum dot but consists of at least three sites of localized charge in
series. The high symmetry and electrical stability of the device allowed us to
triangulate the positions of the different sites of localized charge and find
that one site is located in the island and one in each of the constrictions.
Nevertheless we measure many consecutive single non-overlapping
Coulomb-diamonds in series. In order to describe these findings, we treat the
system as a strongly coupled serial triple quantum dot. We find that the
non-overlapping Coulomb diamonds arise due to higher order cotunneling through
the outer dots located in the constrictions. We extract all relevant
capacitances, simulate the measured data with a capacitance model and discuss
its implications on electrical transport.
