La kolektejo estas apud la merkato.

Yes — it is built from smaller parts:

• kolekt- = the idea of collecting
• -ej- = a place meant for something
• -o = a noun ending

So kolektejo literally means a place for collecting.
This is a very common Esperanto pattern:

• lerni = to learn → lernejo = school, place for learning
• kuiri = to cook → kuirejo = kitchen, place for cooking
• vendi = to sell → vendejo = shop, place for selling

So an English speaker can often learn Esperanto vocabulary by noticing these building blocks.

La is the definite article, meaning the.

In this sentence, both nouns are being treated as specific, identifiable things:

• la kolektejo = the collection point / the collection place
• la merkato = the market

Esperanto has only one definite article: la.
It does not change for gender, number, or case the way articles do in some languages.

Also, Esperanto has no indefinite article. So:

• merkato = a market / market
• la merkato = the market

Because Esperanto verbs do not change according to the subject.

Estas is the present-tense form of esti = to be, and it stays the same with every person:

• mi estas = I am
• vi estas = you are
• li/ŝi/ĝi estas = he/she/it is
• ni estas = we are
• ili estas = they are

So in La kolektejo estas apud la merkato, estas simply means is.

This is one reason Esperanto grammar feels very regular to English speakers.

Apud means something like:

• beside
• next to
• by
• at the side of

It usually suggests fairly close physical position.

It is similar to near, but often a bit more specific. Compare:

• apud la merkato = beside / next to the market
• proksime de la merkato = near the market

And compare with:

• ĉe la merkato = at the market

So apud emphasizes location beside something, not just general nearness.

Because after apud, the noun is normally in its basic form, not the accusative.

So:

• apud la merkato = beside the market

In Esperanto, prepositions usually take the normal noun form.
However, an -n can sometimes appear after a preposition to show direction toward a place, rather than location.

Compare:

• La kolektejo estas apud la merkato. = The collection point is beside the market.
  
  • location
• Mi iras apud la merkaton. = I go to a position beside the market.
  
  • movement toward that location

So in your sentence, it is just describing where something is, so no -n is needed.

Esperanto word order is fairly flexible, because the grammar is marked clearly.

The most neutral order is:

• La kolektejo estas apud la merkato.

But you could also say:

• Apud la merkato estas la kolektejo.

That version puts more focus on the location first, almost like Beside the market is the collection point.

For learners, the original order is the safest and most natural basic pattern:

• subject + verb + prepositional phrase

A helpful breakdown is:

• ko-lek-TE-jo

The stress in Esperanto is almost always on the second-to-last syllable, so the stress falls on TE.

A rough English-style guide:

• ko as in core without the r
• lek like leck
• te like teh
• jo like yo

So roughly: ko-lek-TEH-yo

A more careful point: in Esperanto, j sounds like English y.

It is a perfectly normal kind of Esperanto word formation.

One of the strengths of Esperanto is that speakers can form words very transparently from roots and endings. Even if a learner has never seen kolektejo before, they can often guess it from:

• kolekti = to collect
• -ejo = place for something

Depending on context, kolektejo could mean things like:

• collection point
• collection center
• pickup point
• depot
• place where things are gathered

So yes, it is a natural Esperanto formation, even if the exact English translation may vary by context.

Exactly. Esperanto often uses esti (to be) where English might say:

• is
• is located
• is situated

So:

• La kolektejo estas apud la merkato.

can naturally mean:

• The collection point is beside the market.
• The collection point is located beside the market.

Esperanto usually prefers the simpler verb unless there is a reason to be more formal or specific.

Grammatically, bare nouns are possible in Esperanto, but in this sentence removing la would usually make it sound less natural unless the context is very special.

Compare:

• La kolektejo estas apud la merkato.
  = a specific collection point is beside a specific market

If you say:

• Kolektejo estas apud merkato.

it sounds more like a very context-dependent or unusually generic statement, and most of the time it would not be the best choice.

So for a normal sentence referring to known places, keeping la is the right choice.