Celestial distribution of the 30 597 galaxies analysed in the SPRING catalogue, distributed over nearly one-fourth of the northern sky. They represent the totality of galaxies in the spring sky within cz < 10 000 km s⁻¹ and r < 17.7 mag. The colours represent the overdensity parameter Δρ/⟨ρ⟩ (defined in Sect. 2.3.1) for galaxies in four bins of local galaxy overdensity (red = UH, green = H, blue = L, black = UL). In the left panel, the third dimension emphasises the overdensity parameter. The highest narrow peak represents the Coma cluster, the second narrow peak is A1367, and the broader peak is Virgo.