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EXPERIENCE NEW WAYS OF BEING

Legal, professionally-guided 5-day psychedelic group retreats in the Netherlands and Costa Rica

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UPCOMING SYNTHESIS-LED RETREATS IN 2025:

 
February 23 - 27: Costa Rica
April 6 - 10: The Netherlands
August 16 - 20: The Netherlands
October 7 - 11: The Netherlands
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Medical Safety

Safety

Our team of professionals perform comprehensive health screenings for all applicants in order to identify any personal health risks, ensuring the safety of all of our participants.

BEST PRACTICES

Best
Practices

The Synthesis Team consists of experienced professionals trained in the best practices used in research trials; they have prepared and guided more than 1,100 participants safely through the full variety of psychedelic experiences.

SCIENTIFICALLY VALIDATED

Scientifically Validated

Through our legacy collaboration with the Psychedelic Research Group at Imperial College London, Synthesis has contributed to pioneering 21st-century data.

Your Experience Could Include:

  • Peak experiences

  • Mystical states of consciousness

  • Overcoming destructive attachments

  • Deep and lasting sense of connection

  • Remembering meaningful memories

  • Challenging and confronting visions

  • Processing childhood experiences

  • Synesthesia — see sounds

  • Experiences of intense love and bliss

  • Identify and release suppressed feelings

  • Intellectual epiphanies

  • Enhanced self-acceptance and compassion

  • Heightened states of creativity

*While there are no guarantees as to what kind of journey you will have - these are the most-commonly known types of psychedelic experiences.

AS SEEN IN MEDIA:

1,100+ people have embarked on a journey through Synthesis — They happily share with you how it has impacted their lives

“The experience has been nothing short of life changing. From the facilitators, to the people I shared the venue with, everyone was warm, caring, and accepting. The Synthesis team is doing amazing work, long may it continue. I can't wait to attend again!”
— William, 37, Recruitment, UK
“It would be impossible for me to speak too highly of the benefits of undergoing the Synthesis psilocybin retreat. The guidance offered, in the in the weeks leading up to the retreat itself, through the care and commitment of the facilitators before, during and after the ceremony/experience, coupled with the offer of support and assistance, guarantees (to those who ensure they arrive with the right mindset) a successful outcome. I took away from my time in Amsterdam a foundation which I know I can continue to build on in the years to come.

My perception of the benefits I've gained have already been confirmed by those near and dear to me and already the benefits have extended beyond the merely personal into my deepest relationships. This has been one of the most truly transformative experiences I've ever undergone. It is without question unlike any of the other modalities I have undertaken over many years and clearly the one that to date has had the most significant impact in enabling me to understand who I am, why I have lived my life as I have to date and what I will now do with what of it remains.”
— Stewart, 62, Insurance, Australia
“For those of us searching for meaning or redirection, Synthesis and its facilitators can help you self-guide to what is your higher calling or purpose.”
— Lauren, 34, Accountant, USA
“I really appreciated the way the Synthesis team was informative, educational and to the point and at the same time sacred and ceremonial. Last but not least I appreciated how they were kept totally secular, that is important to me. What struck me as surprising was that the actual psychedelic journey was a much lesser piece of the overall experience than I had expected. I did expect the surrounding activities to be nice and interesting, but not that they would be essential to the experience and the possibility to learn from it in the way that they turned out to be.”
— Jonah, 40, Teacher, Sweden
“I couldn't think of a better place for a psilocybin retreat. The Synthesis team is very loving and supportive, the building modern and beautiful, the food lovingly prepared. I am glad that I took part and I will come again.”
— Marcel, 53, Teacher, Switzerland
“The Synthesis team is amazing, from the first email to the emotional goodbye hug they are top class every step of the way. Having been to many spiritual/development focused retreats (meditation, motivational speakers, etc) this was one of the most professionally run and knowledgeable I’ve ever been to. Also, as a complete novice to entheogens/psychedelics it was amazing to see how the retreat catered to those of all levels, helping a rookie like me feel very safe & secure while still keeping those with more experience really engaged! Lastly, they do a great job of curating groups of awesome people, while our group was very diverse there was no drama or issues. Amazing experience, people and team!”
— Daniel, 27, Market Research & Analytics, Canada
“This retreat allowed me to explore areas in my life I had not been able to easily access. Everyone was professional and lovingly compassionate and caring. A beautiful experience.”
— Marion, 66, Psychotherapist, USA

Your Journey Starts Here:

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