Planctae

In Greek mythology, the Planctae (Greek: Πλαγκταὶ, Planktai, "Wanderers") or Wandering Rocks were a group of rocks, between which the sea was mercilessly violent. The Argo (led by Jason) was the only ship to navigate them successfully (with divine help from Hera, Thetis, and the Nereids). Jason chose to brave the Planctae instead of braving Scylla and Charybdis.