Last week, 62 survivors, people evacuated from neighbouring blocks and supporting families, made the trip with only one of them having visited the area before.
The group, aged between seven weeks and 64 years old and including 30 children, visited local attractions and took part in activities such as water sports and a zip wire.
Hanan Wahani, who used to live on the ninth floor of Grenfell Tower, lost her brother's family-of-five who lived on the 21st floor in the fire.
The primary school teacher, a mother-of-two, said the "calm and gentle atmosphere" of Cornwall encouraged her to let out her pain.
"I will forever remember what happened to us and our devastating loss, but being in Cornwall encouraged me to recall the good memories I shared with those I lost," she said.
The families stayed together at the University of Exeter's Cornwall campus at Penryn, also visiting local attractions including a farm, the Eden Project and St Michael's Mount.
The group had therapy sessions of massage, reflexology, sound therapy, sculpture and singing workshops.
Local food included cream teas, fish and chips on the Swanpool beach, ice creams and lunch on Gyllyngvase beach.
The break was arranged by mother Esme Page after she watched television reports of the disaster from her home in Truro, 280 miles away.
She posted on Facebook six days after the blaze and founded Cornwall Hugs Grenfell, arranging holidays for those affected.
The project, which is set to run until 2019, provided free holidays for families in individual cottages throughout the summer.
"I came up with the idea on the day of the fire, watching the coverage but I restrained for a few days because I thought it would be too difficult and complex," Ms Page said.
"Then I felt compelled that I had to do it. I posted on Facebook and the response was overwhelming."
Her Facebook post on June 20 read: "Imagine if we could put a Cornish holiday on the horizon of every Grenfell resident and firefighter family: a time to rest, a time to let our beautiful county bless these people and work its gentle magic."
Since then, the project had received more than 200 pledges of accommodation and vouchers from local businesses for attractions and meals.
Firefighters from Falmouth acted as minibus drivers for the group holiday.
Ms Page described the holiday as "a rich, humbling week", adding many guests felt it had re-built something of the community they lost.
Dany Duncan, of ElementalUK watersports centre, co-ordinated the transport for the holiday as well as providing two days of watersports.
"I was bowled over by the positivity of everyone we took on the water. Young and old, they all wanted to have a go," Mr Duncan said.
The group holiday was oversubscribed and Cornwall Hugs Grenfell aims to offer another break in October or February half-term.
It is appealing for property owners and large accommodation providers, particularly where visitors do not require a car, to pledge units for these times.
Donations can be made at justgiving.com/crowdfunding/cornwallhugsgrenfellphase2
Additional reporting by Press Association