godan verb (-ru), intransitive verb
reach a stage; arrive at a decision; attain
Used for arriving at an abstract endpoint: a conclusion, state, level, or result. Often follows に.
交渉は合意に至った。
The negotiations reached an agreement.
彼は努力の末、成功に至った
After much effort, he attained success.
godan verb (-ru), intransitive verb
in the extreme case of
Fixed pattern ～に至っては meaning 'when it comes to...' or 'in the case of...', often highlighting an extreme or noteworthy example.
彼に至っては、全く反省の色がない。
In his case, there is no sign of remorse at all.
godan verb (-ru), intransitive verb
Archaic use for physical arrival or resulting in something. Modern Japanese prefers 来る or 着く for physical arrival.
古語では「いたる」が単に「来る」の意で使われた。
In classical language, いたる was used simply to mean 'come'.