Learn Hardcore Finnish: Aamulla bussin meno on hidasta ruuhkan takia. - In the morning the bus ride is slow because of the traffic jam.

Aamulla is the adessive case of aamu (morning). Literally it’s “at/on the morning,” but in idiomatic English it corresponds to “in the morning.”

In Finnish, times of day are very often expressed in the adessive:

aamulla = in the morning
päivällä = in the daytime / in the afternoon
illalla = in the evening
yöllä = at night

So you don’t normally say *aamuna for “in the morning”; aamulla is the standard form for that time expression.

Why is it bussin meno and not just bussi? What does this structure mean?

Bussin meno is literally “the bus’s going / the bus’s movement.” It’s built from:

bussin = genitive of bussi (bus) → “of the bus”
meno = going, movement, flow, travel

Together they form a noun phrase that refers to how the bus is moving or how the bus traffic is flowing, not the physical bus itself.

Compare:

Aamulla bussi on hidas. = In the morning the bus is slow. (focus on the vehicle, or e.g. its schedule)
Aamulla bussin meno on hidasta. = In the morning the bus’s movement is slow. (focus on traffic flow / progress of the ride)

In traffic-related contexts, Finnish often talks about meno (going/movement) rather than the object:

Liikenteen meno on hidasta. = Traffic flow is slow.

What does meno mean here, and how is it related to things like meno–paluu?

Meno is a noun from the verb mennä (to go). Its core meanings:

going, movement, progress
trip / outbound journey (as in ticket types)
sometimes: “situation / happening / atmosphere” in colloquial speech (e.g. Siellä oli kova meno = It was wild there)

In this sentence, bussin meno is sense 1: the going/movement of the bus.

In meno–paluu, you see another meaning:

meno = outward journey
paluu = return

So meno–paluu-lippu = return ticket / round-trip ticket (literally “outward-and-return ticket”). The root idea, “going,” is the same.

Why is it hidasta and not hidas? Isn’t hidas the basic form of “slow”?

Yes, hidas is the basic (nominative) form of “slow,” but here it appears as hidasta, which is partitive singular.

In sentences with olla (to be), the describing adjective usually agrees in case with the subject:

Auto on hidas. = The car is slow. (nominative–nominative)

However, with mass-like, abstract, or process-like subjects, Finnish very often uses the partitive to describe a quality that is seen as ongoing, partial, or not a fixed classification:

Liikenne on hidasta. = Traffic is slow.
Elämä on vaikeaa. = Life is hard.

Here bussin meno (the bus’s movement/going) is treated like such a process, so:

Bussin meno on hidasta. = The bus’s movement is slow(-going).

If you said bussin meno on hidas, it would sound more like a permanent, classifying statement, and in this context it would be odd or at least much less natural. Hidasta fits the idea of “it’s slow(-going) right now / in these conditions.”

Why do we say ruuhkan takia and not just ruuhka? What is takia doing here?

Takia is a postposition that means “because of / due to.” It always takes its complement in the genitive case.

ruuhka (traffic jam, congestion)
ruuhkan (genitive: of the traffic jam / of the congestion)
ruuhkan takia = because of the traffic jam / due to congestion

So takia is the element that actually expresses the causal relationship. Without it, ruuhka alone would just mean “traffic jam / congestion,” with no “because of” meaning.

Could we also use vuoksi instead of takia? Is there any difference between ruuhkan takia and ruuhkan vuoksi?

Yes, vuoksi is another postposition meaning “because of / due to.” It behaves like takia, also requiring a genitive:

ruuhkan takia
ruuhkan vuoksi

Both are correct and very similar in meaning. Nuances:

takia is extremely common and completely neutral.
vuoksi can sound a bit more formal or bookish in some contexts, but in everyday speech and writing they usually feel interchangeable.

In this sentence, either ruuhkan takia or ruuhkan vuoksi would work.

Why is ruuhkan in the genitive case? Is that only because of takia?

Yes. Takia is a postposition that governs the genitive, meaning the word before it must be in the genitive:

sateen takia = because of the rain
onnettomuuden takia = because of the accident
ruuhkan takia = because of the traffic jam

So ruuhkan is simply ruuhka put into the genitive to satisfy this rule. Without takia, there would be no reason to put ruuhka in the genitive.

Can the word order of this sentence be changed, and would that change the meaning?

Yes, Finnish allows fairly flexible word order, and changes mainly affect emphasis, not the basic meaning. Some possible variants:

Aamulla bussin meno on hidasta ruuhkan takia.
– Neutral: focuses first on when (in the morning).
Ruuhkan takia bussin meno on aamulla hidasta.
– Fronting ruuhkan takia emphasizes the cause (“because of the traffic jam, the bus’s movement is slow in the morning”).
Bussin meno on aamulla hidasta ruuhkan takia.
– Slightly more focus on the bussin meno (“the bus’s movement is slow in the morning because of the traffic jam”).

All of these are grammatical. The core factual content stays the same; what changes is which part you highlight first.

If I just want to say “In the morning the bus is slow because of traffic,” is Aamulla bussi on hidas ruuhkan takia also correct?

It’s grammatically correct, but the nuance is different.

Aamulla bussi on hidas ruuhkan takia.
– Literally: “In the morning the bus is slow because of the traffic jam.”
– Focus feels more on the bus as an entity being slow (e.g. its timetable, or that particular bus line).
Aamulla bussin meno on hidasta ruuhkan takia.
– Focus is on the movement / progress being slow due to congestion – more natural in the context of traffic conditions.

In normal talk about traffic, Finns are more likely to phrase it like the original sentence (or like Liikenne on aamulla hidasta ruuhkan takia – “Traffic is slow in the morning because of the congestion”).