  Pairs of radio emitting jets with lengths up to several hundred kiloparsecs
emanate from the central region (the `core') of radio loud active galaxies.
  In the most powerful of them, these jets terminate in the `hotspots', compact
high brightness regions, where the jet flow collides with the intergalactic
medium (IGM). Although it has long been established that in their inner
($\sim$parsec) regions these jet flows are relativistic, it is still not clear
if they remain so at their largest (hundreds of kiloparsec) scales. We argue
that the X-ray, optical and radio data of the hotspots, despite their
at-first-sight disparate properties, can be unified in a scheme involving a
relativistic flow upstream of the hotspot that decelerates to the
sub-relativistic speed of its inferred advance through the IGM and viewed at
different angles to its direction of motion. This scheme, besides providing an
account of the hotspot spectral properties with jet orientation, it also
suggests that the large-scale jets remain relativistic all the way to the
hotspots.
