Relativistic jets are feeding radio lobes on spatial scales many time larger than the host galaxy, they are interesting laboratories and probes of many different environments and time scales. Starting from the outermost regions and zooming onto the jet base, I will review some of the recent results in the field. In particular, with increasing resolving power, I will discuss the presence of jet structures in blazar and radio galaxies, focusing in particular on M87 and 3C84. The use of space VLBI (on the latter) and of mm-VLBI (the "Event Horizon Telescope", on the former) are permitting to reach spatial resolution of tens to hundreds Schwarzschild radii, and thus probing the black hole vicinity and the region of jet formation with unprecedented detail. This also has important connection to the high energy emission from jets, which I will also shortly discuss.