The Observatorio Astrofísico de Javalambre (OAJ) is a new Spanish astronomical facility particularly designed for carrying out large sky surveys. The OAJ is mainly motivated by the development of J-PAS, the Javalambre- PAU Astrophysical Survey, an unprecedented astronomical survey that aims to observe 8500 deg2 of the sky with a set of 54 optical contiguous narrow-band filters (FWHM ~14 nm) and 5 mid and broad-band ones. J-PAS will provide a low resolution spectrum (R ~ 50) for every pixel of the Northern sky down to AB~22:5 - 23:5 per square arcsecond (at 5 σ level), depending on the narrow-band filter, and ~ 2 magnitudes deeper for the redder broad-band filters. The main telescope at the OAJ is the Javalambre Survey Telescope (JST/T250), an innovative Ritchey-Chrétien, alt-azimuthal, large-etendue telescope with a primary mirror diameter of 2.55m and 3 deg (diameter) FoV. The JST/T250 is the telescope devoted to conduct J-PAS with JPCam, a panoramic camera of 4.7 deg2 FoV and a mosaic of 14 large format CCDs that, overall, amounts to 1.2 Gpix. The second largest telescope at the OAJ is the Javalambre Auxiliary Survey Telescope (JAST/T80), a Ritchey-Chrétien, German-equatorial telescope of 82 cm primary mirror and 2 deg FoV, whose main goal is to perform J-PLUS, the Javalambre Photometric Local Universe Survey. J-PLUS will cover the same sky area of J-PAS using the panoramic camera T80Cam with 12 filters in the optical range, which are specifically defined to perform the photometric calibration of J-PAS. The OAJ project officially started in mid 2010. Four years later, the OAJ is mostly completed and the first OAJ operations have already started. The civil work and engineering installations are finished, including the telescope buildings and the domes. JAST/T80 is at the OAJ undertaking commissioning tasks, and JST/T250 is in AIV phase at the OAJ. Related astronomical subsystems like the seeing and atmospheric extinction monitors and the all-sky camera are fully operative. This paper aims to present a brief description and status of the OAJ main installations, telescopes and cameras. The current development and operation plan of the OAJ in terms of staffing organization, resources, observation scheduling, and data archiving, is also described.