VLBI at APEX: First fringes

We have equipped the APEX telescope for 1 mm VLBI and obtained first fringes on 3C 279 at 229 GHz in May 2012 with SMA (Hawaii) and SMTO (Arizona). The fringe spacing achieved was 29 microarcseconds, adequate to directly observe strong-field general-relativistic effects around the black hole in the Galactic center by resolving the expected diameter of the shadow of the event horizon in Sgr A* of ∼ 40 microarseconds. I present on behalf of the collaboration the unusual aspects of this high-altitude VLBI installation, and the prospects for upcoming observations with a global array at the highest resolution.