Other boaties, harbourmasters and marine officials would have noticed the distinctive vessel, which now has an alert out on it, Mrs Holland said.
"It's not a classic boat but it is a one-off design, built in 1980. She's a lovely boat, quite unusual, and people were always admiring it."
The $145,000 yacht has recently been advertised for sale on TradeMe. Although the Hollands planned to sell the fibre glassed, triple skinned kauri cutter, the decision to give up the boat they've owned and sailed for over 13 years was not made lightly. To lose it to theft has been heartbreaking; the thieves having taken more than "just a boat", Mrs Holland said.
"It had a lot of our personal stuff on board, and all our charts and the log book."
That log book records many voyages, including in the Pacific Islands, periods when the Hollands lived aboard for six months, and shorter sails around Northland and Great Barrier Island with family, including grandchildren.
Marine radio networks have been notified of the yacht's disappearance and all boaties in New Zealand waters and harbours asked to keep an eye out for it. Word is also spreading fast via the internet and sites such as TradeMe. Among the sailing fraternity who have sent emails and messages since news of the theft went online is an American couple the Hollands met while sailing in the Pacific many years ago.
The Hollands heard about the theft when they were late leaving home on Friday morning (Waitangi Day) to go to Opua for a sail. They texted their son, whose yacht is moored next to theirs, and who was also preparing for a long weekend on the briny. He told them he thought they had left earlier because Harlech wasn't at its mooring. The boat is insured.
Northland Regional Council deputy harbour master Chidambaram Surendran said it was unusual for ocean-going yachts to be stolen, while thefts of items from boats were more common. He said the information about Harlech would be sent to harbour and coastal wardens. The marine fraternity would look out for the boat but the theft and follow-up was a police matter.