on the (side of) cliffs

[diamondcutter]

Use the proper forms of the words given to fill in the blanks.

much, visit , build, simple, great, year , from, life, what, it

There are lots of places of interest to visit in Henan. One of the (most) famous places is the Red Flag Canal in Linzhou which was (built) on the side of cliffs of the Taihang Mountains.
...
Source: the English test paper, senior high school entrance exams, Henan province, China, 2021

I have no questions about the answers but the use of the noun “side” in the second sentence above. I’d like to know if “on the side of cliffs” is natural. What about just saying “on the cliffs”?

 

[Tarheel]

The phrase "on the side of cliffs" tells us where it is. The other one makes you guess exactly where on the cliffs it is.

 

[Skrej]

Since it's unusual to have a canal on the side of a cliff, simply using 'on the cliff' would naturally lead us to think the canal runs along the top edge of the cliff.

Since the canal in question is on the side of the cliff, you need to keep 'on the side' to clarify that.

However, judging by the shots in this video, the canal seems to be mostly cut into the side of the cliff, or perhaps run along the base of the cliff in places. I would probably restate it as something like 'was built in the side of cliffs along the Taihang Mountains'.

 

[diamondcutter]

1. The road is in the side of the cliff of the mountain.
2. The road is on the side of the cliff of the mountain.

For this picture, I should say sentence #1. Am I right?

 

[Tarheel]

What a picture! I would say the road is cut into the mountain. If you have to use "cliff" either "in" or "on" is fine with me.

 

[Tdol]

Some the images of the canal on Google look much the same as the road.