  VBr$_3$ is a van der Waals antiferromagnet below the N\'eel temperature of
26.5 K with a saturation moment of 1.2 mB/f.u. above the metamagnetic
transitions detected in the in-plane and out-of-plane directions. To reveal the
AFM structure of VBr$_3$ experimentally, we performed a single-crystal neutron
diffraction study on a large high-quality crystal. The collected data confirmed
a slight monoclinic distortion of the high-temperature rhombohedral structure
below 90 K. The magnetic structure was, nevertheless, investigated within the
R-3 model. The antiferromagnetic structure propagation vector k = (1, 0, 0.5)
was revealed. In an attempt to determine the magnetic structure, 72
non-equivalent magnetic reflections were recorded. The experimental data were
confronted with the magnetic space groups dictated by the R-3 lattice symmetry
and propagation vector. The best agreement between the experimental data and
the magnetic structure model was obtained for the space group P-1.1'_c. The
magnetic unit cell of the proposed unique antiferromagnetic structure with
periodicity 6c is built from two identical triple layers antiferromagnetically
coupled along the c axis. Each triple layer comprises a N\'eel
antiferromagnetic monolayer sandwiched between two antiferromagnetically
coupled ferromagnetic monolayers.
