  We report observations of carbon recombination lines near 34.5 MHz (qunatum
number n=578) and 325 MHz (n=272) made towards Cas A, the Galactic centre and
about ten other directions in the galactic plane. Constraints on the physical
conditions in the line forming regions are derived from these and other
existing observations. The CII regions that produce the low-frequency lines are
most likely associated with the neutral HI component of the ISM.
