Al final del recorrido, compramos una postal de la galería y otra de la exposición.

In Spanish, al final de... is the usual way to say at the end of....

• al = a + el
• del = de + el

So:

• al final = at the end
• del recorrido = of the tour/route

En el final is much less natural here. A Spanish speaker would normally say al final del recorrido.

Recorrido literally means a route, course, or walk-through. In this sentence, it suggests the path or tour someone followed, for example through a museum, gallery, or exhibition space.

Depending on context, you might translate it as:

• tour
• route
• walk-through
• visit around the exhibition

It is a little more specific than visita, because recorrido focuses on moving through a place.

That phrase is an introductory time expression, and Spanish often puts a comma after that kind of phrase, especially in careful writing.

So the comma helps separate:

• Al final del recorrido = time/background information
• compramos... = main action

It is similar to English:

• At the end of the tour, we bought...

In very short sentences, the comma is sometimes omitted, but here it is perfectly natural.

It can mean either one, because for -ar verbs, the nosotros form is the same in the:

• present: compramos = we buy
• preterite: compramos = we bought

Here, the context makes it clear that it means we bought:

• Al final del recorrido... suggests a completed event in the past.

This is very common in Spanish: context often tells you which meaning is intended.

The sentence describes a completed action: at the end of the tour, they bought the postcards. That is exactly the kind of situation where Spanish normally uses the preterite.

So:

• compramos here = we bought as a finished event

If the sentence were describing an ongoing habit or background situation, the imperfect might be used instead, but not here.

Because Spanish often leaves out a noun when it is already understood. This is called ellipsis.

So:

• una postal de la galería y otra de la exposición

means:

• one postcard from the gallery and another postcard from the exhibition

The second postal is omitted because it would be repetitive.

You could also say:

• una postal de la galería y otra postal de la exposición

But the version without the repeated noun sounds more natural.

In Spanish, otro / otra normally means another by itself. You do not usually say un otro or una otra.

So:

• otra = another one
• otra postal = another postcard

That is different from English, where another historically comes from an + other, but in modern Spanish, otra already does the job on its own.

In Spanish, postal meaning postcard is feminine:

• la postal
• una postal
• otra postal

That is why the article and the adjective/pronoun are feminine too:

• una
• otra

This is something learners usually just need to memorise, because the ending -al does not automatically tell you the gender.

Here, de shows a relationship, but the exact English translation depends on context.

So:

• una postal de la galería could mean:
  • a postcard of the gallery
  • a postcard from the gallery
  • a postcard about the gallery

And:

• otra de la exposición could mean:
  • another postcard of/from/about the exhibition

In a museum or gallery context, it often means a postcard connected with that place or exhibition, either depicting it or sold there.

Because the sentence refers to specific things:

• the gallery
• the exhibition

The definite article la shows that these are known or identifiable in the context.

So:

• de la galería = of/from the gallery
• de la exposición = of/from the exhibition

Without the article, the meaning would sound more general or less natural here.

Yes, you could, but the nuance changes slightly.

• la visita = the visit as a whole
• el recorrido = the route or walk-through through the place

So:

• Al final de la visita = at the end of the visit
• Al final del recorrido = at the end of the tour/path through the exhibition or gallery

Both are natural, but recorrido focuses more on the actual movement through the space.

Yes. Spanish word order is flexible.

For example, you could also say:

• Compramos una postal de la galería y otra de la exposición al final del recorrido.

That still makes sense. But putting Al final del recorrido first is very natural because it sets the scene before the main action.

It is similar to English:

• At the end of the tour, we bought...