Overview of the HH 80/81 giant outflow in an Hα mosaic from the APO 3.5 m telescope obtained with the 30 Å bandwidth filter. This image has had a large-scale intensity gradient removed. The blue oval shows the location of IRAS 18162-2018 (GGD 27) and the approximate orientation of the radio jet emerging from this source. Yellow lines surrounding GGD 27 show the approximate location and spatial extent of the outflow cavity walls as traced in Spitzer 8 and 24 μm images. Dashed red circles mark the locations of various shocks and radio features. A blue circle near the top marks the location of radio source 34 at the suspected end of the radio jet. The magenta oval marks the location of the infrared dark cloud (IRDC) discussed in the text. A red “X” symbol near the source region marks the B2/B3 star located at the center of the circular near-IR H₂ bubble discussed in the text. The small, unlabeled, dashed circle near the bottom along the radio jet axis marks the location of a diffuse Hα knot which is also shown in Figure 13.