The protest, organised by the Refugee Rights Action Network, started with a night vigil at the centre on Friday leading into the main protest on Saturday.
Shire of Northam president Steven Pollard said the protest did not cause any major problems for the shire and police who patrolled the area reported no major incidents.
‘The police kept everything well under control,’ Mr Pollard said.
RRAN refugee advocate Sarah Ross said detention centres were in regional or remote areas to keep them ‘out of sight and out of mind’.
‘By protesting, we draw attention to these remote facilities and to the fact that we are still locking up asylum seekers in contravention to international law,’ Ms Ross said.
‘These people are being locked up without any right to trial or charge in indefinite detention. This means they have absolutely no idea when they will be released ” if ever.
Ms Ross said the RRAN believed mandatory detention was unnecessary, inefficient and inhumane.
‘Detention is a system that directly results in the deterioration of the mental health of those incarcerated within it.
‘Yongah Hill is no exception to this mental health epidemic and there has already been substantial evidence that the mental health of those inside has already started to deteriorate.
‘It is time we started rethinking how we treat asylum seekers, with humanity and respect and by introducing alternative measures such as increasing resettlement.’
Ms Ross said the organisation had not planned any future protests at the Yongah Hill centre.
‘But this may change, depending on the conditions inside the centre and if the treatment worsens,’ she said.