This growing popularity leads to Japan's first major winter sports event, which is the 1972 Sapporo Winter Olympics, which was also the first Winter Olympics to be held in Asia, right? So not just a significant milestone for Japan, but also for the continent.

hold 開催する⇒be held 開催された

milestone マｲﾙｽﾄｰﾝ n)マイル標石⇒重要な時点、画期的な出来事

continent コﾝﾃｨﾈﾝﾄ n)大陸

not only/just/merely but also

Not just is daily exercises good for your body, (but) also for mental. 

Not only is English useful for traveling but also for

He is not only popular but also smart.

He is not only a comedian but also a singer.

The singer not only sings but also entertains a lot of people.

The singer loves not only to sing but also to dance.

The singer is famous not only in Japan but also in the U.S.

Not only the singer but also you like apples. その歌手だけでなく貴方もリンゴが好きだ。

Not only does he likes apples but he also loves pineapples. ⇒倒置文

彼はリンゴが好きだけでなくパイナップルも大好きだ。

merely ミｱﾘｰ adv)ただ...にすぎない、単に...するだけ（onlyより改まっている）