Schematic view on the central ≲5 pc. N₂H⁺(1–0) is indicated by green contours of [4, 32] × σ (=0.07 Jy beam^-1 km s^-1), CS(5–4) shown as blue contours of [8, 48] ×σ (=0.08 Jy beam^-1 km s^-1), and CH₃OH(8–7) indicated by white contours of [3, 6, 96] ×σ (=0.06 Jy beam^-1 km s^-1) on a NIR HST NICMOS (1.87 μm) image (HST archive). Red crosses in the triop, SEE, and the V cloud show the class I methanol masers (see text) and the black cross Sgr A*.