Latin colō 'to inhabit, to dwell' (hence in-cola 'inhabitant', in-quil-īnus 'tenant') is derived by Indo-Europeanists from PIE *kwel- 'to turn', assuming the original meaning was 'to turn up soil'. However, this explanation strikes me as a bad one, so I searched for a better etymology.
I see here a PIE A root *kwel- 'to dwell' (homonymous with the above one) cognate to PAltaic *gù:lí 'dwelling, cottage'. This is in turn related to PNC *qəlV 'house, hut', which gives also Kartvelian *xl- 'to dwell' (hence *sa-xl- 'house' and PIE B *sel- 'dwelling, settlement' (Latin solum, PGermanic *sala-), an instance of Fournet's Law1.
1 See my earlier post for more information.