Distribution of detected 6.7 GHz methanol maser velocity with respect to Galactic longitude. Black crosses represent detections of known sources in the GLOSTAR survey and red crosses represent new detections. The coloured spiral arms are as follows: magenta is 3 kpc, red is Norma-Outer, blue is Scutum Centaurus, green is Sagittarius Carina, and yellow is Perseus. The dashed lines represent the updated spiral arm models of Taylor & Cordes (1993) as used in, e.g. Schuller et al. (2021) while the solid lines are the spiral arm descriptions from Reid et al. (2019). The background shows the CO emission from Dame et al. (2001).