  We have studied the FR I radio galaxy NGC 6251 and its environment at several
wavelengths and scale lengths. On the large scale, we have probed the gravity
field by measuring the velocity dispersion of the cluster members associated
with NGC 6251 and relating this to the cluster's X-ray emission. On the small
scale, the gravitational information is provided by cold HI near the nucleus
and the distribution of stars and gas near the centre of the galaxy. The cold
HI gas which we have measured explains the absorption of the central X-ray
emission and is consistent with the extinction through the recently discovered
HST gas disc of NGC 6251.
