The study re-examines the structure of the nerve net in *Hydra*, a simple nervous system found in cnidarians. Using a novel pan-neuronal antibody (PNab), the authors reveal that *Hydra* has two distinct nerve nets: one in the ectoderm and one in the endoderm. Confocal imaging shows that these nerve nets are separate structures, with no direct connections between them. Transmission electron microscopy (TEM) and serial block face scanning electron microscopy (SEM) further demonstrate that the nerve nets consist of bundles of parallel overlapping neurites, which include different neural circuits. The bundles are linked by circuit-specific gap junctions, indicating that the nerve cells within these bundles form specific synaptic connections. The authors also confirm that the nerve net grows continuously by lateral addition of new nerve cells to existing bundles, as evidenced by tracking newly differentiated nerve cells. The findings provide insights into the dynamics and organization of the *Hydra* nervous system, highlighting the unique architecture and connectivity of its nerve nets.The study re-examines the structure of the nerve net in *Hydra*, a simple nervous system found in cnidarians. Using a novel pan-neuronal antibody (PNab), the authors reveal that *Hydra* has two distinct nerve nets: one in the ectoderm and one in the endoderm. Confocal imaging shows that these nerve nets are separate structures, with no direct connections between them. Transmission electron microscopy (TEM) and serial block face scanning electron microscopy (SEM) further demonstrate that the nerve nets consist of bundles of parallel overlapping neurites, which include different neural circuits. The bundles are linked by circuit-specific gap junctions, indicating that the nerve cells within these bundles form specific synaptic connections. The authors also confirm that the nerve net grows continuously by lateral addition of new nerve cells to existing bundles, as evidenced by tracking newly differentiated nerve cells. The findings provide insights into the dynamics and organization of the *Hydra* nervous system, highlighting the unique architecture and connectivity of its nerve nets.