These long, crazy-looking clouds can grow to be 600 miles long and can move at up to 35 miles per hour, causing problems for aircraft even on windless days.

Known as Morning Glory clouds, they appear every fall over Burketown, Queensland, Australia, a remote town with fewer than 200 residents. A small number of pilots and tourists travel there each year in hopes of “cloud surfing” with the mysterious phenomenon.

Similar tubular shaped clouds called roll clouds appear in various places around the globe. But nobody has yet figured out what causes the Morning Glory clouds.

This shot was captured by photographer Mick Petroff from his plane near Australia’s Gulf of Carpenteria.