The narrow gap with a width from 0.7 to 1m is flanked tightly by two cliffs. A gleam of sky can be spied through the gap, so it’s known as  "A Gleam of Sky". It is a gully formed when the granite body was weathered and eroded by running water along its vertical fractures (joints) and then suffered gravitational collapse.

What is romantic is that the total number of stone steps here is 299 which means "everlasting love" according to its Chinese pronunciation. For this reason, many lovers carve their names in a heart-shaped lock which they lock on an iron chain in memory of their love.

Running water intensely weathered and eroded the granite along its internal vertical fractures (joints).

With unceasing weathering and erosion, the fissures gradually expanded.

A nearly vertical gully was formed.

                                 （1）                                 （2）                                 （3）