„entlang“ is a postposition, not a normal preposition — it comes after its noun instead of before it.

So you say

     die Straße entlang

     not

     ❌ entlang die Straße

🔹 Detailed explanation

1. Most German prepositions go before the noun:

Examples:

1. auf dem Tisch – on the table
2. unter dem Bett – under the bed
3. an der Wand – on the wall

So normally:

preposition + noun

2. But entlang is special:

It is a postposition, meaning it comes after the noun phrase it governs.

✅ Correct:

1. die Straße entlang – along the street
2. den Fluss entlang – along the river
3. den Weg entlang – along the path

❌ Incorrect:

1. entlang die Straße
2. entlang den Fluss
3. entlang den Weg

3. Why German allows this

Historically, entlang developed from a combination of ent (out) + lang (long).

It literally meant “the length of (something)”, so speakers kept it after the noun to sound natural — “(the street) the-length-of”.

That’s why its position stayed postpositive.

4. Can it ever come before the noun?

Yes — but rarely, and it sounds formal or poetic, and it changes the case from accusative → genitive or dative.

✅ Example (formal/written):

Entlang des Flusses stehen Bäume.

→ Along the river stand trees.

     Here, entlang is before the noun and takes genitive (des Flusses).