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Apr 19 1943

April 19th, 1943: “Bicycle Day” Albert Hofmann Take’s Humanity’s First Acid Trip

Lysergic Acid Diethylamide-25, commonly known as Acid or LSD, was the psychotropic agent of choice for the1960s psychedelic revolution begun in Haight-Ashbury. But the first human LSD voyage occurred in World War II Europe under very different circumstances than one might expect…


Though LSD was first synthesized in 1938, it was not until 1943 that the first human LSD trip was recorded.  Albert Hofmann, a chemist at Sandoz Laboratories in Switzerland, had synthesized several derivatives of ergot, a fungus found on rye, in search of a new stimulant pharmaceutical to induce childbirth.  After accidentally absorbing a small amount of his 25th derivative during synthesis, Hofmann noticed some strange effects, and felt:


“… affected by a remarkable restlessness, combined with a slight dizziness. At home I lay down and sank into a not unpleasant intoxicated-like condition, characterized by an extremely stimulated imagination. In a dreamlike state, with eyes closed (I found the daylight to be unpleasantly glaring), I perceived an uninterrupted stream of fantastic pictures, extraordinary shapes with intense, kaleidoscopic play of colors. After some two hours this condition faded away.”


Three days later, on April 19th 1943, Hofmann decided to intentionally ingest 0.25 milligrams of his LSD-25 to confirm the true effects of the new drug.  He believed this tiny amount to be a threshold dose, but soon realized he had underestimated the potency of his discovery. Within an hour, Hofmann was experiencing the radical mental perception shifts of humanity’s first acid trip.  Since wartime restrictions prevented the use of motor vehicles, he asked his lab assistant to escort him home by bicycle, and hence the date became known as “bicycle day”.  Once home on his couch and assured by his physician that he was not fatally poisoned, Hofmann began to enjoy his “trip”:


“… little by little I could begin to enjoy the unprecedented colors and plays of shapes that persisted behind my closed eyes. Kaleidoscopic, fantastic images surged in on me, alternating, variegated, opening and then closing themselves in circles and spirals, exploding in colored fountains, rearranging and hybridizing themselves in constant flux…”


After his bicycle day experience, Hofmann realized he had made a remarkable discovery. He saw incredible potential in LSD for use in psychotherapy, but because of its “intense and introspective nature”, he never imagined LSD would have popular appeal.  Little did he know that this new drug would go on to become a major catalyst in the development of the 1960s counter-culture, with the Haight-Ashbury as its ground zero. From the 1960s onward, the San Francisco Bay Area came to be known to the growing global psychedelic community as the “acid triangle,” where the majority of the world’s LSD supply was produced and distributed.  This is very likely still the case today.