One of the major public transportation in Europe refers to subway. The first one was opened in 1863

Transportation is a vital aspect numerous modern big cities. One of the major public transportation in Europe refers to subway. The first subway was opened in 1863 and located in London.

In Europe, three of largest underground rail services are located in London, Paris, and Moscow. Each of the cities has its own uniqueness. London was the first city that launched the underground rail system and introduced the method for subway tracks called "cut and cover". Paris has a beautiful decoration in the station with myriad of artworks, such as paintings, mosaics, and sculptures. The last, Moscow the city with a large number of tracks lying above the ground. Eventually, the underground rail system expanded the service in case of its benefit for the people.

Transportation is a vital aspect for numerous big modern cities. (Dear Miss dils, you can look at the material "word order" to have better understanding about that)

One of the major public transportations in Europe refers to subway.

The last, Moscow was the city with a large number of ...

That is a quite understandable essay.
However, I would give some suggestions..

Transportation is a vital aspect [for] numerous modern big cities.
... transportation in Europe refers to[is] subway.
>> you need preposition (for) to divide the noun phrase
>> in my opinion, 'refers to' in this sentence is a little bit strange, then probably you can change it into linking verb (is)

the station with myriad of artworks,
>> 'myriad' is adjective. Hence, you should make it to the noun phrase
or
if you still want to make 'myriad' as a noun, then you should give 'a' in front of it (a myriad of artworks)

thank you..
I hope it helps..