Though he failed to find the herb, he encountered Jeongbang Falls on the way and he left his autograph, Seobul Gwaji (which literally means "Seobul was here"), on the cliff wall, where it no longer remains. An inscription on the wall of the waterfall saying "Seobulgwacha", refers to Seobul's journey.
Even though he did not locate the herb, he encountered Jeongbang Falls and left his name, Seobul Gwaji (meaning "Seobul was here"), on a cliff near the falls. An inscription at the waterfall site that reads "Seobulgwacha" relates to Seobul's expedition.