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This paper presents the first H  i results extracted from the South African Radio Astronomy Observatory (SARAO) MeerKAT Galactic Plane Survey (SMGPS) – a narrow strip (Δ b ∼ 3°) along the southern Milky Way. The primary goal consisted in tracing the great attractor (GA) wall across the innermost zone of avoidance. We reduced a segment spanning the longitude range 302° ≤ ℓ ≤ 332° for the redshift range z ≤ 0.08. The superb SMGPS sensitivity (rms = 0.3–0.5 mJy beam−1 per 44 km s−1 channel) and angular resolution (∼31″ × 26″) lead to a detection limit of log(M H  i /M⊙) ≥ 8.5 at the GA distance (⁠|$\mbox{$V_{\rm {hel}}$}\, \sim 3500{\!-\!}6500$|  km s−1). A total of 477 galaxy candidates were identified over the full redshift range. A comparison of the few H  i detections with counterparts in the literature (mostly HIZOA) found the H  i fluxes and other H  i parameters to be highly consistent. The continuation of the GA wall is confirmed through a prominent overdensity of N  = 214 detections in the GA distance range. At higher latitudes, the wall moves to higher redshifts, supportive of a possible link with the Ophiuchus cluster located behind the Galactic Bulge. This deep interferometric H  i survey demonstrates the power of the SMGPS in improving our insight of large-scale structures at these extremely low latitudes, despite the high obscuration and continuum background. [ABSTRACT FROM AUTHOR]

The Local Void is one of the nearest large voids, located at a distance of 23 Mpc. It lies largely behind the Galactic Bulge and is therefore extremely difficult to observe. We use H  i 21 cm emission observations from the SARAO MeerKAT Galactic Plane Survey (SMGPS) to study the Local Void and its surroundings over the Galactic longitude range 329° < ℓ < 55°, Galactic latitude | b | < 1.5°, and redshift cz < 7500 |$\rm km \, s^{-1}$|⁠. We have detected 291 galaxies to median rms sensitivity of 0.44 mJy per beam per 44 |$\rm km \, s^{-1}$| channel. We find 17 galaxies deep inside the Void, 96 at the border of the Void, while the remaining 178 galaxies are in average density environments. The extent of the Void is ∼58 Mpc. It is severely underdense for the longitude range 350° < ℓ < 35° up to redshift z < 4500 |$\rm km \, s^{-1}$|⁠. The galaxies in the Void tend to have H  i masses that are lower (by approximately 0.25 dex) than their average density counterparts. We find several potential candidates for small groups of galaxies, of which two groups (with 3 members and 5 members) in the Void show signs of filamentary substructure within the Void. [ABSTRACT FROM AUTHOR]