Vi går ned til havnen om aftenen.

Går is the present tense form of gå.

• at gå = to go / to walk
• går = go / are going / walk / are walking

In a normal Danish main clause, you need the finite verb, so you use går, not the infinitive gå.

Also, Danish verbs do not change for person the way English sometimes does. So:

• jeg går = I go
• vi går = we go
• de går = they go

The form går stays the same.

It can mean either, depending on context.

At gå very often means to walk, so this sentence may suggest going there on foot. But in natural translation, English may still simply say we go down to the harbor in the evening if the walking aspect is not important.

So:

• gå = walk / go on foot
• but in some contexts it is translated more generally as go

If Danish wanted to emphasize using transport, it would usually use another verb, such as kører.

Ned means down. It is a directional adverb.

In Vi går ned til havnen, it adds the idea of movement downward or down toward that place. In English, this matches down to the harbor.

Sometimes this is literal, and sometimes it is just the natural way to describe movement toward a place, especially a waterfront, lower area, or a place conventionally thought of as down there.

Without ned, Vi går til havnen would still mean We go to the harbor, but it would lose that extra sense of direction.

They do different jobs:

• ned = direction (down)
• til = destination (to)

So:

• ned til havnen = down to the harbor

This is very similar to English, where you also often use both words:

• We go down to the harbor

If you remove til, the sentence would not work the same way, because til is what links the movement to the destination.

Because havnen is the definite form: the harbor.

Danish usually adds definiteness as an ending on the noun:

• en havn = a harbor
• havnen = the harbor

So til havnen means to the harbor.

English uses a separate word (the), but Danish often puts the definite marker at the end of the noun instead.

Because in Danish, a noun normally takes the suffixed definite article by itself:

• havnen = the harbor

You usually use den with an adjective or for special emphasis:

• den store havn = the big harbor
• den havn = that harbor / that particular harbor

So in a simple phrase like to the harbor, Danish naturally uses til havnen, not til den havn.

Because om aftenen is an idiomatic time expression in Danish.

With recurring times of day, Danish often uses:

• om morgenen = in the morning
• om dagen = in the daytime / during the day
• om aftenen = in the evening / in the evenings
• om natten = at night / during the night

So om aftenen is the normal expression here. It often suggests something habitual or general, not just one specific evening.

This is a very common and important distinction:

• om aftenen = in the evening / in the evenings
  
  • often general or habitual
• i aften = tonight / this evening
  
  • one specific evening

So:

• Vi går ned til havnen om aftenen = We go down to the harbor in the evening / in the evenings.
• Vi går ned til havnen i aften = We’re going down to the harbor tonight.

Most naturally, om aftenen makes it sound habitual or general:

• We go down to the harbor in the evenings

But Danish present tense can also sometimes refer to the near future, depending on context.

So går itself does not force only one interpretation. The surrounding words and situation decide.

In this sentence, the time phrase om aftenen strongly points toward a routine or usual behavior.

Because that is a very natural Danish word order.

The basic structure here is:

• Vi = subject
• går = verb
• ned til havnen = place/direction
• om aftenen = time

Danish main clauses follow the verb-second rule, so when the subject comes first, the verb usually comes second:

• Vi går ...

After that, adverbials such as place and time are fairly flexible, but putting the time expression at the end is completely normal.

You could also say:

• Om aftenen går vi ned til havnen.

That puts more emphasis on in the evening.

Yes. That would still be correct.

• Vi går til havnen om aftenen = We go to the harbor in the evening.
• Vi går ned til havnen om aftenen = We go down to the harbor in the evening.

The version with ned adds a more vivid sense of direction and is often the more natural choice if the harbor is thought of as being down there or down by the water.