connective N1 uncommon written

〜に至る — to reach (the point/place of) ~

〜に至る・にいたる

Meaning

to reach / arrive at / lead to (a notable, often grave, endpoint after a long process)

長年ながねんの対立たいりつが、ついに戦争せんそうに至いたった。

Years of conflict finally led to war.

Attaches to	Form	Example
Noun or dictionary-form verb	N ／ V-る + に至る

When: Formal/written — stresses arriving at a serious or extreme endpoint.

何度なんども話はなし合あった末すえ、離婚りこんするに至いたった。

After talking it over many times, they ended up getting divorced.

資金不足しきんぶそくで、計画けいかくは中止ちゅうしに至いたった。

Owing to a lack of funds, the project came to be cancelled.

Idioms: に至っては ('when it comes to ~, even ~') and に至っても ('even after reaching ~'). Geographic extent: 東京とうきょうから大阪おおさかに至いたる区間くかん ('the stretch from Tokyo to Osaka').

Jengo shows 〜に至る the way you actually meet it: inside real Japanese sentences, so it sticks instead of staying an abstract rule.

Sources Compiled from published Japanese grammar references.