  We present radio maps of the head-tail radio galaxy, 3C 129 at 240 and 610
MHz using the Giant Metrewave Radio Telescope. We have studied in detail the
morphology of the source and the distribution of spectral index over the
object. We find large-scale spectral steepening along the jet away from the
core. Using synchrotron spectral ageing theory, we infer the age (time since
particle acceleration) of electrons at various locations along the jet and
ascribe an age of $\sim$200 Myr to 3C 129. We find that the "Crosspiece" has a
spectral index of ${\sim}-1$, similar to the jet, which is not consistent with
the suggestion by Lane et al. (2002) that it could be a radio relic. We have
also studied 3C 129.1 and the other sources in the field.
