A rock arch is a doorway shaped by time rather than by hands, so tradition reads it as a passage into a new stage that has been forming slowly. Walking under it is seen as crossing a threshold you did not have to build yourself.
Where in your waking life have you met something like this lately?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.