The position-velocity diagram of the ¹³CO 1–0 line summed over the whole W43 latitude range (−0.5° to 0.3°) and plotted against its longitude. Contours go from to 0.4 to 2.0 by 0.4 K. The two most prominent structures, W43-main and W43-south, appear to be linked by lower density clouds. The two main bridges identified between W43-main and W43-south (blue bars) are outlined by red curves which are continuous when they correspond to filaments clearly identified by Motte et al. (in prep.) and dashed or dotted for weaker clouds connections. The location of a few 870   μm continuum peaks and reference sources are also indicated.