I found a nice cafe near Nishi-Takasihmadaira station when running.
I found a nice coffee shop near Nishi-Takasihmadaira station when jogging.
「～があった」は、この場合、「私は～を見つけた」という表現が適切かと思いますので、ここでは"I found"としました。
「～していたら」は、「～をしていた時に」ということになりますので、"when（～する時）"と、過去進行形の文章を用います。省略せずに節で表すと、"when I was running （私ががランニングしていた時）"となります。ここでは、"I found" と "I was running"の二つの文章の中で主語がどちらも"I"と、同じであることから、"when running"のように主語・Be動詞を省略しています。
カフェは、"coffee shop"という言い方もしますが、今はもともとフランス語である"cafe"という言葉の方がよく使われるかもしれませんね。
ランニングには、runningもしくはjoggingを使います。joggingの方が、ゆっくりリラックスして走っている感じでしょうか。
ご参考になれば幸いです！
While jogging, I found a nice cafe near Nishi-Takashimadaira station.
I found a cafe I like near Nishi-Takashimadaira station while jogging.
The other day, while I was jogging, I found a really cool cafe near Nishi-Takashimadaira station.
It is great to find new places where we can enjoy a meal, sometimes we find these places by chance, this means it happens without planning.
If you would like to explain that you found a new cafe by chance on a day that you went jogging, use the sentences above.
"Finding this restaurant was by chance, I was jogging that day and happened to see it near the Nishi-Takashimadaira station."
食事をするのに新しい場所を見つけるのはうれしいですよね。find these places by chanceとは、たまたま見つけるという意味です。
ジョギングをしていた日に、たまたま新しいカフェを見つけたことを伝えるには、これらの例がぴったりです。
"Finding this restaurant was by chance, I was jogging that day and happened to see it near the Nishi-Takashimadaira station."
（このレストランたまたま見つけたんだ。その日ジョギングをしていて、西高島平駅の近くにたまたま見えたんだ。）
While I was jogging, I stumbled upon a nice cafe near Nishi-Takashimadaira station
During my morning run yesterday, Ifound a nice cafe.
Sometimes while running or jogging, we find some really nice places that we did not expect to find, when this happens it's a welcome surprise. We can uise the following sentences:-
1. While I was jogging, I stumbled upon a nice cafe near Nishi-Takashimadaira station.
The expression "stumbled upon" means to find something that we did not expect or was not looking for.
2.During my morning run yesterday, Ifound a nice cafe.
ランニングやジョギングをしていると、偶然素敵なお店に出会ったりすることがありますね、うれしい驚きです。次のように言えます。
1. While I was jogging, I stumbled upon a nice cafe near Nishi-Takashimadaira station.
（ジョギングをしていたら西高島平駅の近くにいいカフェを見つけました）
"stumbled upon" は「偶然～を見つける」という意味です。
2.During my morning run yesterday, I found a nice cafe.（昨日の朝ランニングをしていていいカフェを見つけました）
I was out for a run and I found a nice cafe near Nishi-Takashimadaira station.
I found a really nice cafe near Nishi-Takashimadaira station while I was out for a jog.
The two sentences you see provided above are great ways to express to your listener that you found a nice cafe near Nishi-Takashimadaira station while you were running. Often we say we are out for a run or out for a jog. This simply means you were running or jogging. This is a common way to refer to running or jogging, it would make a great addition to your vocabulary.
どちらも「ランニングをしていたら西高島平駅の近くにいいカフェを見つけた」のすごくいい言い方です。
'out for a run' または 'out for a jog' はよく使われる表現です。これはシンプルに「ランニングをして／ジョギングをして」という意味です。これは「ランニング／ジョギング」を表す一般的な表現です、ぜひ語彙に加えておいてください。
When I was running, I came across a nice cafe near Nishi-Takashimadaira station.
As I was jogging, I stumbled upon a lovely cafe close to Nishi-Takashimadaira station.
You can use the phrasal verb 'come across' to express finding something by chance. Running is faster than jogging.
You could also use 'stumble upon' which is another phrasal verb and has the same meaning as 'come across' ie. to find accidentally.
"When I was jogging/running, I found a nice cafe near Nishi-Takashimadaira station"
"I discovered this really nice cafe near Nishi-Takashimadaira station when I was jogging"
If you wanted to explain that when you were jogging/running you found a nice café near Nishi-Takashimadaira station, you could simply state: "When I was jogging/running, I found a nice cafe near Nishi-Takashimadaira station" or "I discovered this really nice cafe near Nishi-Takashimadaira station when I was jogging".
「ジョギング／ランニングしていたら西高島平駅の近くにいいカフェを見つけた」は、次のように言えます。
"When I was jogging/running, I found a nice cafe near Nishi-Takashimadaira station"（ジョギング／ランニングしてたら西高島平駅の近くにいいカフェを見つけた）
"I discovered this really nice cafe near Nishi-Takashimadaira station when I was jogging"（ジョギングしてたら西高島平駅の近くにいいカフェを見つけた）
While jogging near Nishi-Takashimadaira station, I came upon a delightful little cafe.
While jogging in the vicinity of Nishi-Takashimadaira station, I found a gem of a cafe.
While jogging near Nishi-Takashimadaira station, I came
upon a delightful little cafe.
The phrase "çame upon" means that you happened to
discover something by chance (by accident). The adjective
delightful means pleasant, great, lovely.
While jogging in the vicinity of Nishi-Takashimadaira station,
I found a gem of a cafe.
The phrase "a gem of a cafe" means that it is a truly
fantastic place that sells wonderful things.
While jogging near Nishi-Takashimadaira station, I came upon a delightful little cafe.（西高島平駅の近くをジョギングしていたら、素敵なカフェを見つけた）
"came upon" は「偶然見つけた」という意味です。"delightful" は「楽しい／素晴らしい／素敵な」という意味の形容詞です。
While jogging in the vicinity of Nishi-Takashimadaira station, I found a gem of a cafe.（西高島平駅の近くをジョギングしていたら、素敵なカフェを見つけた）
"a gem of a cafe" は「本当にいいカフェ」という意味です。
日本 
南アフリカ 
カナダ 
アメリカ合衆国 
イギリス 
