Vi har en hurtig omstigning i Odense, så vi må ikke gå for langt fra perronen.

Omstigning means a transfer or change from one train, bus, etc. to another.

In travel Danish, en omstigning is very common for the situation where you arrive on one service and need to continue on another. It is especially common in timetables, station announcements, and travel apps.

Because omstigning is an en-word (common gender noun).

With an en-word in the singular indefinite, the adjective usually stays in its basic form:

• en hurtig omstigning

If it were an et-word, you would normally add -t:

• et hurtigt skift

So hurtig is correct here because it describes en omstigning.

Danish often uses har in this kind of situation to describe what is part of the journey or situation:

• Vi har en hurtig omstigning = we have a quick transfer

It sounds natural in Danish, even though English might also say something like We only have a short transfer or We have to change quickly.

A more action-based Danish version could be:

• Vi skal hurtigt skifte tog

But the sentence with har focuses on the transfer as a situation rather than the action itself.

Here så means so or therefore.

It links the first idea to the consequence:

• Vi har en hurtig omstigning i Odense
• så vi må ikke gå for langt fra perronen

So the second part explains what follows from the first part.

Må ikke usually means must not, may not, or are not allowed to.

But in real usage, it can also express a practical necessity, not just a rule. In this sentence, it probably does not mean that there is an official rule against leaving the platform area. It more likely means:

• we really shouldn’t go far
• we can’t afford to go far
• it would be a bad idea to go far because the transfer is short

So må ikke can sound stronger than English shouldn’t, but in context it often means practical necessity.

Because må is the finite verb, and in a normal Danish main clause the finite verb comes early in the sentence, while ikke usually comes after it.

So:

• vi må ikke gå

This is very normal Danish word order.

A useful pattern is:

• subject + finite verb + ikke
  • infinitive

For example:

• Jeg kan ikke komme
• Vi vil ikke vente
• Hun må ikke gå

For before an adjective or adverb often means too.

So:

• for langt = too far

Compare:

• for dyrt = too expensive
• for sent = too late
• for hurtigt = too fast

In the sentence, gå for langt fra perronen means go too far away from the platform.

Because fra means from or away from, and the idea here is distance away from the platform.

So:

• gå fra perronen = go away from the platform
• gå for langt fra perronen = go too far away from the platform

This is different from:

• på perronen = on the platform

The sentence is about not moving too far away from that place.

Because Danish uses the definite form here: perronen = the platform.

The ending -en is the usual definite ending for many en-words:

• en perron = a platform
• perronen = the platform

It is definite because the speaker means a specific platform: the one connected to their journey or transfer.

Because i is the normal preposition for being in a city, country, or many geographical places.

So:

• i Odense
• i København
• i Danmark

Since Odense is a city, i is the natural choice here.

In this sentence, så works as a linking word meaning so / therefore, and the clause after it keeps normal main-clause order:

• så vi må ikke gå...

That is very natural.

You can also see Så må vi ikke gå... in other contexts, where så is more like a sentence opener meaning then / so. That version puts så in first position and causes inversion:

• Så må vi ikke gå for langt fra perronen

Both are possible in Danish, but the version in your sentence is a very common way to connect cause and consequence.