10かい（ ）京都（きょうと）にいきました。
a. か b. で c. に d. も

The sentence without the brackets means “I went to Kyoto 10 times” and it is OK as it is. However, if I want to emphasize “10 times” and say “as many as 10 times” then I would add d. も there.

More examples:

ジョンさんはハンバーガーを5いつつも食たべた。
John ate as many as 5 hamburgers.
昨日きのうは12じゅうに時間じかんも寝ねた。
I slept as long as 12 hours yesterday.
エマさんはセーターを8枚はちまいも編あんだ。
Emma knitted as many as 8 jumpers.
ヤンさんには兄弟きょうだいが九人きゅうにんもいる。
Jan has as many as 9 siblings (brothers and sisters).
メグさんは10ページものレポートを書かいた。
Meg wrote a report as many as 10 pages long.
えっ？コーヒーにさとうを三みっつも入いれるんですか？
What? Do you have 3 sugars in your coffee?
トシさんは毎日まいにち10キロも走はしる。
Toshi runs as long as 10 km every day.

Note that this も is always used after a number + counter.

も in the meaning of “too” or “also”

ジョンさんもハンバーガーを5いつつ食たべた。
John also ate 5 hamburgers.
エマさんはセーターも8枚はちまい編あんだ。
Emma knitted 8 jumpers also (as well as something she knitted 8 of).
ヤンさんにも兄弟きょうだいが九人きゅうにんいる。
Jan also has 9 siblings (as well as somebody else who has 9 siblings).
トシさんも毎日まいにち10キロ走はしる。
Toshi also runs 10 km every day.

For more study material for JLPT N4 exam, please visit JLPT N4 Grammar and Vocab and JLPT N4 Kanji pages.