Die waterpunt is by die kilometermerker.

Because both waterpunt and kilometermerker are definite nouns.

In Afrikaans, die means the. Unlike in some other languages, Afrikaans does not change the definite article for masculine, feminine, or neuter nouns. It is simply die for all of them.

So:

• die waterpunt = the water point
• die kilometermerker = the kilometer marker

Waterpunt is a compound noun.

Afrikaans very often joins nouns together into one word. Here:

• water = water
• punt = point

So waterpunt literally means water point, usually a place where water is available, such as a refill station or water stop.

This is very common in Afrikaans. English often writes such expressions as two words, while Afrikaans often writes them as one.

It is another compound noun:

• kilometer = kilometer
• merker = marker

So kilometermerker means kilometer marker.

It refers to a marker showing distance, for example along a road, route, or trail.

This is the normal basic word order for a simple statement in Afrikaans:

• subject
  • verb
    • rest of the sentence

So here:

• Die waterpunt = subject
• is = verb
• by die kilometermerker = location phrase

This is very similar to English:

• The water point
  • is
    • by the kilometer marker

Here, by means something like:

• at
• by
• near

So is by die kilometermerker means the water point is located at or near the kilometer marker.

It does not usually mean possession here. It is a preposition showing location.

Not always.

By often means at, by, or near, but it does not always mean directly beside something. If you want to be more exact about right next to, Afrikaans might use a more specific expression depending on context.

So in this sentence, by die kilometermerker is best understood as at the kilometer marker or near the kilometer marker, not necessarily touching it or immediately beside it.

Yes. Is in Afrikaans is the present-tense form of to be used here, and it looks exactly like English is.

In this sentence:

• Die waterpunt is by die kilometermerker
• The water point is by the kilometer marker

Afrikaans verbs are often simpler than English verbs because they usually do not change much for different subjects in the present tense.

Yes, normally they do.

Unlike German, Afrikaans does not capitalize all nouns. So common nouns such as:

• waterpunt
• kilometermerker

are written with lowercase letters unless they begin the sentence.

That is why the sentence starts with Die capitalized, but waterpunt is lowercase.

A rough English-style guide would be:

duh VAA-ter-punt is bay duh ki-LOH-me-ter-mer-ker

A few notes:

• Die is often pronounced roughly like duh in everyday speech.
• water in Afrikaans is not exactly like English water; the a is broader.
• by sounds like bay.
• g does not appear in this sentence, so there is no need for the harsh Afrikaans g sound here.

Pronunciation can vary a little by accent, but this guide is close enough for a learner.

Yes, you could.

Naby means near. So:

• Die waterpunt is by die kilometermerker = The water point is at/by the kilometer marker
• Die waterpunt is naby die kilometermerker = The water point is near the kilometer marker

The version with by can sound a bit more like the location is associated with that marker. The version with naby focuses more clearly on nearness.

Yes, if you mean a rather than the.

For example:

• ’n waterpunt = a water point
• ’n kilometermerker = a kilometer marker

So:

• Die waterpunt is by die kilometermerker = The water point is by the kilometer marker
• ’n waterpunt is by ’n kilometermerker = A water point is by a kilometer marker

Using die tells us the speaker has a specific water point and a specific marker in mind.

It is natural and clear, especially in practical contexts like:

• hiking routes
• races
• trail maps
• road directions
• event instructions

The compound nouns may feel a little technical because they are very precise, but they are completely normal Afrikaans. The sentence sounds like useful directional or informational language.