We have updated the catalogs of Galactic HII regions, giant molecular clouds (GMCs), and 6.7-GHz methanol masers to outline the spiral structure of our Galaxy. The related parameters have been collected and (re)calculated based on the data in the literature. In particular, for each spiral tracer, we list the photometric or trigonometric distance, and/or the solutions of the kinematic distance ambiguity (KDA) when available. The kinematic distances when adopted are calculated using a flat rotation curve with two sets of R_0_, {Theta}0, and solar motions, where one set is the IAU standard and the other is from the new observational results. The rotation curve of Brand & Blitz (1993, Cat. J/A+A/275/67) is also used to derive the kinematic distances.

Cone search capability for table J/A+A/569/A125/tablea1 (HII regions as tracers of spiral arms)

Cone search capability for table J/A+A/569/A125/tablea2 (Giant molecular clouds)

Cone search capability for table J/A+A/569/A125/tablea3 (6.7-GHz methanol masers)