  Understanding the ground state of many-body fluids is a central question of
statistical physics. Usually for weakly interacting Bose gases, most particles
occupy the same state, corresponding to a Bose--Einstein condensate. However,
another scenario may occur with the emergence of several, macroscopically
populated single-particle states. The observation of such fragmented states
remained elusive so far, due to their fragility to external perturbations. Here
we produce a 3-fragment condensate for a spin 1 gas of $\sim 100$ atoms, with
anti-ferromagnetic interactions and vanishing collective spin. Using a
spin-resolved detection approaching single-atom resolution, we show that the
reconstructed many-body state is quasi-pure, while one-body observables
correspond to a mixed state. Our results highlight the interplay between
symmetry and interaction to develop entanglement in a quantum system.
