Two things happened in the mid 1940's that changed the world forever: the first atomic bomb was detonated and the psychedelic discovery of LSD occurred—an explosion of material and spiritual discoveries both happened nearly simultaneously; a very peculiar historical happening if you care to compare these two synchronous global events.
April 19 has splashed into the collective global consciousness as being recognized as Bicycle Day. You could say it's the first psychedelic holiday of our modern world. To celebrate it you can enjoy a beautiful day, ride a bicycle or take a celebratory sacrament in a consciously laid set and setting.
Over the next few years, [Albert Hoffman] worked his way through the lysergic acid derivatives, eventually synthesizing LSD-25 for the first time in 1938. After minimal testing, LSD-25 was set aside as he continued with other derivatives. Four years later, on April 16, 1943, he re-synthesized LSD-25 because he felt he might have missed something the first time around. That day, he became the first human to experience the effects of LSD after accidentally ingesting a minute amount. Three days later, on April 19, 1943, he decided to verify his results by intentionally ingesting 250 ug of LSD. This day has become known as "Bicycle Day" as Hofmann experienced an incredible bicycle ride on his way home from the lab.