text: Glen Johnson said he was stepping down from Cadwgan Building Preservation Trust (CBPT) due to the harassment from a small number of unnamed people.
  He said some had taken exception to the way the castle project was being run. It reopened in April.
  The trust, made up of 250 people, secured revamp funds, with more than £6m from the Heritage Lottery Fund.
  Volunteers raised more than £200,000 to save the 900-year-old site.
  Mr Johnson said: "The main reason for my resignation is to protect my family from the virtual persecution currently being dealt out by a small number of individuals who have taken exception to the castle and its trustees because the project is not precisely as they would like it."
  He will continue to work as a volunteer with the group.
  CBPT chairwoman Jann Tucker said: "Glen's remarkable knowledge of the castle and the history of Cardigan has played a huge part in making the site what it is today and we are pleased that he will continue to support us in the capacity of a volunteer - a role he first took up 30 years ago."
target: A trustee of a group which secured the £12m restoration of Cardigan Castle has quit due to online "persecution".