Learn Hardcore Spanish (Latin America): Mi tía sueña con subir un volcán activo cuando tenga más tiempo. - My aunt dreams of climbing an active volcano when she has more time.

Using de (soñar de) is not standard in modern Spanish in this meaning, and saying mi tía sueña subir… without con sounds incorrect to native speakers in this context.

Another common pattern is:

Soñar que + verb:
Anoche soñé que subía un volcán.
= Last night I dreamed that I was climbing a volcano.

Why is it subir (infinitive) and not a conjugated verb like sube?

After soñar con, when you talk about an action in general (not tied to a specific time), Spanish normally uses the infinitive:

Soñar con + infinitive
Sueño con viajar a México.
I dream of traveling to Mexico.

So:

sueña con subir un volcán activo
she dreams of climbing an active volcano

If you conjugate the verb, you change the structure and the meaning:

Sueña que sube un volcán activo.
She dreams that she climbs / is climbing an active volcano.
→ This sounds more like a literal dream while sleeping, describing the scene.

What exactly does sueña con mean here: is it a literal dream while sleeping or a wish/goal?

It can mean either, depending on context, but in this sentence it most naturally suggests a wish or ambition:

Mi tía sueña con subir un volcán activo cuando tenga más tiempo.
= She dreams of / really wants to climb an active volcano someday.

If you clearly want the meaning of a sleep dream, Spanish often uses soñar que + verb:

Anoche soñó que subía un volcán activo.
Last night she dreamed she was climbing an active volcano.

So:

soñar con + infinitive → usually “dream of doing” (goal/desire)
soñar que + verb → often “dream that (in sleep)”

Why is it un volcán activo and not el volcán activo?

Un here means “a / some (unspecified)”. Your aunt does not have a particular volcano in mind; it’s just “an active volcano” in general.

un volcán activo = an active volcano (any one)
el volcán activo = the active volcano (a specific one we already know about)

So:

Sueña con subir un volcán activo.
She dreams of climbing an active volcano (in general).

If you said:

Sueña con subir el volcán activo.

it would sound like there’s a particular volcano everyone in the conversation already knows about.

Why is the adjective after the noun: volcán activo and not activo volcán?

In Spanish, the normal order is:

noun + adjective

So you say:

un volcán activo = an active volcano
una casa grande = a big house

Putting the adjective before the noun (activo volcán) is either wrong or would sound like very poetic or unusual language. For everyday speech, always say volcán activo.

Why is it subir un volcán and not subir a un volcán?

With subir:

subir algo often means to climb / go up something (treating it as a direct object)
- subir la montaña = climb the mountain
- subir las escaleras = go up the stairs

So subir un volcán = to climb a volcano.

You can sometimes hear subir a with a place, but the nuance changes a bit:

Subir a la montaña can mean “go up to the mountain” (as a destination).
Subir la montaña focuses more on the action of climbing the mountain itself.

For an activity like mountaineering, subir un volcán is very natural in Latin American Spanish.

Could I use escalar instead of subir for climbing a volcano?

Yes, but the nuance is slightly different:

subir un volcán: the most neutral, common way to say “climb a volcano / go up a volcano”.
escalar un volcán: sounds a bit more technical or sporty, like mountain-climbing or rock-climbing as an activity.

Both are understandable. For everyday speech about a personal goal, subir un volcán activo is very natural and common.

Why does the sentence use tenga and not tiene in cuando tenga más tiempo?

This is the subjunctive. In Spanish, after cuando:

You use the subjunctive when talking about a future or uncertain situation.
You use the indicative for habitual or past actions.

Here, cuando tenga más tiempo refers to a future, not-yet-real moment:

Mi tía sueña con subir un volcán activo cuando tenga más tiempo.
= …when she has more time (in the future / someday).

Compare:

Cuando tengo tiempo, leo.
When I have time, I read. (habitual, general fact → indicative: tengo)
Cuando tenga tiempo, te llamo.
When I have time (later), I’ll call you. (future, not certain → subjunctive: tenga)

So tenga is correct here because it’s a future, hypothetical condition.

What does más tiempo add? Is it different from just cuando tenga tiempo?

Yes, there’s a small nuance:

cuando tenga tiempo
= when she has time (any free time at all)
cuando tenga más tiempo
= when she has more time (than she has now)

So más suggests that right now she doesn’t have enough time, but in the future she expects to have extra or additional time that will allow her to do something big, like climb a volcano.

Why is it Mi tía and not just Tía? Do I always need the possessive?

You often use a possessive (mi, tu, su, nuestro…) with family members to say my/your/her…:

Mi tía = my aunt
Su tía = his/her/their/your (formal) aunt

Spanish can sometimes omit the possessive if it is obvious from context (especially with close family like mamá, papá), but:

At the beginning of an isolated sentence like this, Mi tía… is the natural way to say My aunt…

Just saying Tía sueña con subir un volcán… is more like using “Auntie” as a name, the way a child might say “Auntie dreams of…”, and would usually need context (talking directly to that aunt or about a specific aunt everyone knows).

Why is there an accent on tía and what’s the difference between tía and tia?

The accent in tía (the í) marks the stress of the word and helps keep the normal pronunciation rules.

tía is pronounced roughly TEE-ah (two syllables, stress on tí).
tia without an accent would not be correct spelling in Spanish.

Also, note that ñ in sueña is a different letter from n:

sueña is pronounced like “sweh-nyah” (with a ny sound, like in canyon).
suena (without the tilde) is a different verb: sonar = to sound / ring.

So the accents and tildes (í, ñ) are essential; they change meaning and pronunciation.

What tense is sueña and how is soñar conjugated?

Sueña is:

Present tense, 3rd person singular (he/she/it/you formal) of soñar.
soñar is a stem‑changing verb: o → ue.

Present indicative:

yo sueño
tú sueñas
él / ella / usted sueña
nosotros / nosotras soñamos
ustedes / ellos / ellas sueñan

So Mi tía sueña = My aunt dreams / My aunt dreams of…