Learn Hardcore Finnish: Juhannuksena menemme kesämökille, jossa on pieni rantasauna ja vanha laituri. - At Midsummer we go to the summer cottage, which has a small lakeside sauna and an old pier.

So menemme means we go or we are going. In context with a known future time (Juhannuksena), it is naturally understood as we will go (then) even though Finnish uses present tense.

Why is it kesämökille and not just kesämökki? What does the ending -lle mean?

Kesämökki = summer cottage.

Kesämökille has the allative case ending -lle, which typically means:

to, onto, to the place of something

So:

kesämökki – a summer cottage (basic form)
kesämökille – to the summer cottage

In this sentence:

menemme kesämökille = we go to the summer cottage

The allative is very common with places you go to spend time at:

menen rannalle – I go to the beach
menemme mummille – we go to grandma’s (house)
menemme kesämökille – we go to the summer cottage

Could you also say kesämökkiin instead of kesämökille? What is the difference?

Yes, kesämökkiin is also grammatically correct, but the nuance is slightly different.

kesämökille (allative, -lle):
- often feels like to the cottage (as a place / property)
- common for talking about going to your cottage in a general, habitual way
kesämökkiin (illative, -iin):
- more literally into the cottage (inside the building)

In practice:

Juhannuksena menemme kesämökille – normal, idiomatic way to say we are going to the (family) cottage for Midsummer.
Juhannuksena menemme kesämökkiin – focuses more on going into the building, used less for the general cottage trip idea.

So the given sentence uses kesämökille because we are talking about going on a cottage trip, not about physically entering the indoor space.

What is jossa, and how is it related to joka?

Jossa is a relative pronoun in a locative case. It combines:

joka = which / that / who (relative pronoun)
inessive case -ssa = in / inside

So roughly: jossa = in which, where.

In the sentence:

kesämökille, jossa on pieni rantasauna ja vanha laituri
→ to the summer cottage, where there is a small lakeside sauna and an old pier.

Here, jossa refers back to kesämökille and introduces a relative clause describing the cottage. Finnish does not repeat the noun:

English: …to the summer cottage, *which has…*
Finnish: …kesämökille, jossa on… (…to the cottage, in which there is…)

Other forms of joka for reference:

joka – which, that, who
jossa – in which, where
josta – from which
johon – into which, to which
jolla – on which, with which (allative)

Why is there a comma before jossa?

Finnish uses a comma to separate the main clause from a subordinate clause (like a relative clause).

Main clause: Juhannuksena menemme kesämökille
Relative clause: jossa on pieni rantasauna ja vanha laituri

The relative clause starting with jossa adds extra information about the cottage. Standard Finnish punctuation puts a comma before this clause:

…kesämökille, jossa on…

This is similar to English:

…to the summer cottage, where there is…

What does rantasauna literally mean? Why is it written as one word?

Rantasauna is a compound noun:

ranta = shore, beach, waterfront
sauna = sauna
→ rantasauna = a sauna by the water, e.g. a lakeside or seaside sauna.

In Finnish, related nouns are very often combined into a single compound word instead of being written separately. Writing them apart can sound wrong or even change the meaning.

So:

ranta sauna (two separate words) would look incorrect to a Finn.
rantasauna is the correct compound form.

Other examples:

rautatieasema (rauta + tie + asema) = railway station
kirjahylly (kirja + hylly) = bookshelf

Why are the adjectives pieni and vanha in that exact form, and why do they come before the nouns?

Pieni = small, vanha = old.

In Finnish, adjectives usually come before the noun they modify, and they agree with the noun in:

number (singular/plural)
case (nominative, partitive, etc.)

In the clause:

jossa on pieni rantasauna ja vanha laituri

we have an existential structure with on, where:

rantasauna and laituri are in nominative singular, because they are the new items that exist there.
their adjectives pieni and vanha are also nominative singular to match:
- pieni rantasauna – a small lakeside sauna
- vanha laituri – an old pier

If they were plural, you would see:

pienet rantasaunat – small lakeside saunas
vanhat laiturit – old piers

In the part jossa on pieni rantasauna ja vanha laituri, what is the subject of on?

This is an existential clause, a common Finnish structure:

joss(a) – indicates the location (where)
on – the verb is / there is
pieni rantasauna ja vanha laituri – the things that exist at that place

In Finnish grammar, in such clauses the things that exist are treated as the logical subject, but in form they stay in nominative case and usually appear after the verb.

So:

jossa on pieni rantasauna ja vanha laituri
literally: where is a small lakeside sauna and an old pier
naturally in English: where there is a small lakeside sauna and an old pier.

The location word (jossa) is not the subject; it just sets the place.

How do we know whether pieni rantasauna and vanha laituri mean “a small sauna / an old pier” or “the small sauna / the old pier”, since Finnish has no articles?

Finnish does not have articles like a / an / the, so you have to infer this from:

context
what is already known vs. new information

In this sentence:

The speaker is typically talking about their summer cottage and describing what is there.
pieni rantasauna ja vanha laituri are likely specific, known features of that cottage.

In natural English, you would often translate this as:

…where *there is a small lakeside sauna and an old pier.*
or
…where *there is a small sauna and an old jetty.*

But in some contexts it might be:

…where there is *the small sauna and the old pier* (if both speaker and listener already know which sauna and pier they mean).

Finnish leaves this vague; translation chooses a or the depending on context.

Could you also say Juhannuksena menemme kesämökillä instead of kesämökille? What would change?

Kesämökillä is the adessive case (ending -lla / -llä), meaning on / at the cottage.

Compare:

menemme kesämökille – we go to the cottage (allative, -lle)
olemme kesämökillä – we are at the cottage (adessive, -lla)

So:

Juhannuksena menemme kesämökille – we will go to the cottage at Midsummer.
Juhannuksena olemme kesämökillä – we will be at the cottage at Midsummer.

Using menemme kesämökillä would be wrong here; mennä (to go) normally doesn’t take -lla / -llä to mark the destination. You need the allative (to where?) for movement: -lle.

Is Juhannuksena menemme… talking about the future even though the verb is present tense?

Yes. Finnish often uses present tense for future events when the time reference is clear from context.

Here:

Juhannuksena = at Midsummer (a future time point)
menemme = we go / we are going (present form)

Together they are naturally understood as:

We will go to the summer cottage at Midsummer.

There is a separate construction for future-like intention (aiomme mennä = we intend to go), but simple present is very normal for planned future events when a time expression is given.

Is it possible to change the word order, for example Me menemme Juhannuksena kesämökille? Does the meaning change?

Yes, Finnish word order is fairly flexible, and several variants are possible:

Juhannuksena menemme kesämökille, jossa on…
Me menemme Juhannuksena kesämökille, jossa on…
Menemme Juhannuksena kesämökille, jossa on…

All of these are grammatical and essentially mean the same thing. The differences are in emphasis:

Starting with Juhannuksena emphasizes when this happens.
Starting with Me menemme emphasizes the subject we.
Omitting me (menemme) is normal because the -mme ending already shows the subject.

The relative clause jossa on pieni rantasauna ja vanha laituri stays attached to kesämökille, so that part does not move far from kesämökille if you want clear, natural style.