Herschel 70 μm PACS image (0 to 1000 MJy/sr) of the central region around Cyg OB2 (the most massive stars of the cluster are indicated by gray stars). The cross indicates the position of star Cyg OB2 #8 at RA(2000)=20^h33^m16^s and Dec(2000) = 41°18′45′′, frequently used to define the center of Cyg OB2 (e.g., Wright et al. 2015). The H II  regions DR15, 18, 20, and 22 are labelled and the regions shown and discussed in more detail are outlined with dashed lines and numbered.