Μετά την άφιξη στη Ρώμη, θα πάρω το λεωφορείο για το κέντρο.

Because μετά meaning after is followed by the accusative in Modern Greek.

So the noun changes like this:

• η άφιξη = the arrival subject form
• την άφιξη = the arrival object form / after μετά

So μετά την άφιξη means after the arrival or more naturally after arriving.

Yes. μετά την άφιξη and μετά από την άφιξη are both possible.

In sentences like this, μετά την άφιξη is a little more compact and formal-sounding.
You will often hear μετά από in everyday speech too.

So both are correct, but the version in your sentence is perfectly normal.

Greek often leaves out possessive words like my when they are obvious from the context.

Since the sentence already says θα πάρω = I will take, it is clear that the arrival is the speaker’s arrival.

If you wanted to make it explicit, you could say:

• Μετά την άφιξή μου στη Ρώμη... = After my arrival in Rome...

That version is also correct.

στη is the contracted form of σε + τη.

• σε can mean in, at, or to
• τη is the feminine accusative article
• στη = in/to the

Ρώμη is a feminine noun in Greek, so after σε it becomes στη Ρώμη.

In this sentence, the meaning is tied to arrival, so στη Ρώμη is understood as in/to Rome.

That is very common in Modern Greek. The preposition σε covers several meanings that English separates:

• in
• at
• to

The exact meaning comes from context.

For example:

• Μένω στη Ρώμη = I live in Rome
• Πηγαίνω στη Ρώμη = I’m going to Rome
• άφιξη στη Ρώμη = arrival in/to Rome

So you do not need a different preposition here.

It is the normal way to form the simple future in Modern Greek.

• θα
  • verb form
• θα πάρω = I will take

More specifically, Greek usually uses θα with the perfective form here, because the action is seen as a single complete event: one future action of taking the bus.

Because θα πάρω expresses a single complete action: I will take the bus.

Compare:

• θα πάρω = I will take
• θα παίρνω = I will be taking / I will take regularly

So in your sentence, the speaker is talking about one specific future action after arriving in Rome, which is why θα πάρω is the right choice.

This is because Greek verbs often use a different stem for the aorist or perfective forms.

For this verb:

• present: παίρνω = I take
• aorist: πήρα = I took
• perfective form after θα: πάρω = I will take

So πάρω is not a different verb; it is part of the same verb system.

Greek uses the definite article much more often than English.

So θα πάρω το λεωφορείο is a very natural way to say I’ll take the bus, even if English might not be thinking about one previously mentioned bus.

If you said:

• θα πάρω ένα λεωφορείο

that would mean I’ll take a bus, which sounds less specific and less natural in this context.

Yes, για often means for, but here it means something like for / toward / to in the sense of destination.

So:

• το λεωφορείο για το κέντρο = the bus for the center
• natural English meaning: the bus to the center / downtown

In travel and transport contexts, this use of για is very common.

Here το κέντρο usually means the city center, town center, or downtown.

So the sentence is not talking about an abstract center. It means the central part of Rome.

Greek word order is flexible, and time expressions are often placed first.

Starting with Μετά την άφιξη στη Ρώμη sets the time frame first:

• After arriving in Rome, ...

Then the main action follows:

• θα πάρω το λεωφορείο για το κέντρο

This is natural and clear. The comma helps separate the introductory phrase from the main clause.

Yes. A very common alternative would be:

• Όταν φτάσω στη Ρώμη, θα πάρω το λεωφορείο για το κέντρο.

That means When I arrive in Rome, I’ll take the bus to the center.

The sentence with άφιξη is correct, but it sounds a little more formal or written because it uses the noun arrival instead of the verb arrive.