Stamtąd do muzeum jest dalej, ale tamtędy jedzie autobus.

They refer to two different ideas:

• stamtąd = from there → it tells you the starting point
• tamtędy = that way / through there / via that route → it tells you the path or route

So in this sentence:

• Stamtąd do muzeum jest dalej = from that place, the museum is farther away
• ale tamtędy jedzie autobus = but a bus goes that way

Even though the words look similar, they do different jobs.

Because do normally takes the genitive case in Polish when it means to in the sense of toward a destination.

So:

• do muzeum = to the museum

A useful thing to notice is that muzeum looks the same here as in the dictionary form. That is normal for this noun in the singular.

Dalej is the comparative form of daleko:

• daleko = far
• dalej = farther / further

So jest dalej means it is farther.

Here it does not mean continue! or further on. It is about distance.

Because dalej is being used as an adverb, not an adjective.

The sentence is not directly describing a noun like:

• droga jest dłuższa = the road is longer

Instead, it is making a general statement about distance:

• do muzeum jest dalej = it is farther to the museum

Polish often uses this kind of structure with jest + adverb.

Yes, in a way.

English usually needs a subject:

• it is farther

Polish often leaves that kind of it out:

• jest dalej

The idea of it is understood from context: the distance, the route, or getting to the museum from that place.

Polish word order is more flexible than English word order.

So all of these are possible:

• Tamtędy jedzie autobus.
• Autobus jedzie tamtędy.
• Tamtędy autobus jedzie.

They are all grammatical, but they can sound slightly different in emphasis.

In Tamtędy jedzie autobus, the sentence first highlights the route (that way), and then adds the useful fact that a bus goes that way.

Here jedzie means something like:

• goes
• travels
• runs (for a bus route)

The verb jechać is used for traveling by vehicle.

So:

• a person in a car: jedzie
• a train: jedzie
• a bus: jedzie

In this sentence, it most naturally means that a bus goes that way / runs along that route.

It can often suggest a general or practical fact, not only something happening at this exact second.

So tamtędy jedzie autobus is often understood as:

• a bus goes that way
• there is a bus route that goes that way

This is a common use of the present tense in Polish.

Not if you want the same meaning.

• tam = there → location
• tamtędy = that way / through there → route

A bus does not just exist there in the logic of this sentence; it goes by that route. So tamtędy is the right choice.

Ale means but.

It sets up a contrast:

• one disadvantage: from there it is farther to the museum
• one advantage: a bus goes that way

So the sentence balances two facts: the route is longer, but it has public transport.

Yes. That word order is also natural.

Compare:

• Stamtąd do muzeum jest dalej
• Stamtąd jest dalej do muzeum

Both mean the same thing. The difference is mostly about rhythm and emphasis, not basic grammar.

Polish often allows this kind of movement of sentence parts much more freely than English does.

Because both refer back to something away from the speaker, roughly like there / that way.

• tam = there
• stamtąd = from there
• tamtędy = that way / through there

So they are related, but each one adds a different idea:

• from
• route/path

This is very common in Polish: a core location word gets expanded into more specific directional words.