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The early B star S1 in the Rho Ophiuchus cloud excites an HII region and illuminates a large egg-shaped photodissociation (PDR) cavity. The PDR is restricted to the west and south-west by the dense molecular Rho Oph A ridge, expanding more freely into the diffuse low density cloud to the north-east. We recently used upGREAT onboard SOFIA to map the [CII] at 158 micron and [O I] at 63 and 145 micron emission from the S1 PDR. The [C II] and [O I] 63 micron show strong self absorption features leading to extremely complicated spectral profiles. In this talk I will present the results of our recent work that combined the upGREAT/SOFIA data with complementary radio continuum, HI at 21 cm and sub-millimeter molecular line observations to study the distribution of ionized, atomic and PDR gas in the S1 PDR.