kono kukakusaito ha kirei desu.

When は is used as the topic particle, it is pronounced wa, not ha.

So in:

この 区画サイト は きれい です。

the は marks 区画サイト as the topic of the sentence: as for this区画サイト...

This is one of the first pronunciation exceptions learners meet in Japanese:

• は normally = ha as a regular syllable
• は as a particle = wa

The same kind of thing happens with a couple of other particles too, such as へ being pronounced e in many cases.

この is a demonstrative word meaning this.

It must be followed by a noun:

• この 区画サイト = this sectioned site / this campsite plot

This is different from これ, which means this by itself:

• これ = this
• この 区画サイト = this site

So:

• この cannot stand alone here
• it directly modifies the noun that follows it

A useful comparison:

• これ は きれい です。 = This is clean/pretty.
• この 区画サイト は きれい です。 = This site is clean/pretty.

区画サイト is a noun made from two parts:

• 区画 = section, division, partitioned area, plot
• サイト = site

In contexts like camping, 区画サイト often means something like:

• a partitioned campsite
• a camping plot
• a designated site

Japanese often combines a native/Sino-Japanese word with a loanword like this. So it is normal to see:

• kanji + katakana together in one noun

Even if the English translation uses just one natural phrase, the Japanese may be built from smaller parts like this.

Because this sentence is not using a direct object.

The basic structure is:

[topic] は [description] です

So here:

• この 区画サイト は = as for this site
• きれい です = is clean / is pretty

This is a description sentence, not an action sentence. Nothing is being done to the site, so there is no direct object and no を.

Compare:

• この 区画サイト は きれい です。 = This site is clean.
• この 区画サイト を 見ます。 = I look at this site.

The second sentence has a verb acting on something, so it can take を.

Even though きれい ends in い, it is not an -i adjective in modern Japanese grammar. It is a na-adjective.

That is very important, because it affects how it connects to nouns and how it is conjugated.

For example:

• きれいな 区画サイト = a clean/pretty site
• 区画サイト は きれい です = the site is clean/pretty

So きれい behaves like a na-adjective, not like an -i adjective such as あつい or たかい.

This is a common learner point because the ending looks misleading.

Because な is only used when a na-adjective directly modifies a noun.

Examples:

• きれいな 区画サイト = a clean site
• しずかな ところ = a quiet place

But when the adjective comes at the end of the sentence as the predicate, you do not use な:

• 区画サイト は きれい です。
• その へや は しずか です。

So:

• before a noun: きれいな
• at the end of the sentence: きれいです / きれい です

That is why な does not appear here.

です makes the sentence polite and works like a polite copula.

In this sentence, it gives a polite is/am/are type of ending:

• きれい です = is clean / is pretty

Without it, the sentence would be less polite:

• この 区画サイト は きれい。

That version can sound casual, blunt, or conversational depending on context, but textbook Japanese usually teaches です forms early because they are safe and polite.

So です does not add a big new meaning here; it mainly adds politeness and completes the sentence in a standard way.

It can mean either, depending on context.

きれい often covers ideas like:

• clean
• neat
• beautiful
• pretty

So a sentence like this could mean:

• This site is clean
• This site is nice and neat
• sometimes even This site looks beautiful

With a place like a campsite or plot, clean or neat is often the most natural interpretation, but the exact nuance depends on the situation.

This is common in Japanese: one adjective may cover several English words.

Sometimes yes, but the nuance changes.

• は marks the topic
• が often marks the subject with a more focused or identifying feeling

Your sentence:

• この 区画サイト は きれい です。
• natural sense: As for this site, it is clean.

If you said:

• この 区画サイト が きれい です。

it might sound more like:

• This site is the clean one
• This site is the one that is clean
• or it may answer an implicit comparison/question

So は is the more neutral, general choice for simply describing the site.

Yes, but Japanese word order is flexible in a different way from English.

The basic pattern here is:

noun + は + adjective + です

So:

• この 区画サイト は きれい です。

That is the normal and natural order.

Japanese is often described as topic-comment:

• topic: この 区画サイト は
• comment: きれい です

You cannot rearrange it freely in the same way as English. For example, putting この somewhere else would break the noun phrase, because この must stay directly before the noun it modifies:

• correct: この 区画サイト
• incorrect: 区画サイト この

So the structure matters, even though Japanese sometimes allows more flexibility than English in other kinds of sentences.

You are right: normal Japanese writing usually does not use spaces.

This sentence would normally be written as:

この区画サイトはきれいです。

Spaces are often added in beginner materials to make the grammar easier to see:

• この | 区画サイト | は | きれい | です

So the spaces here are a learning aid, not standard real-world punctuation.

As you read more Japanese, you will get used to seeing sentences without spaces and recognizing where words and particles begin and end.