Projections onto the Plane of the masers from Reid et al. (2014), Xu et al. (2016), and Honma et al. (2012) that possess parallax distances and are located within 50 pc from the Plane, superimposed on the dust distribution throughout the Galactic plane. The Sun is at the center of the figure at (0,0). The Galactic center is to the right. The dotted gray line represents the distance beyond which the final resolution of 25 pc cannot be achieved because targets are scarce (see text). We show the spiral arms derived by Reid et al. (2014) (dashed lines, inner and outer parts, together with the local spur of Xu et al. 2016) and Hou & Han (2014) (solid lines). In black we plot Perseus, in blue the Local arm, in magenta we show Sagittarius, and in cyan we plot Scutum.