Los sábados voy al cajero automático que está frente al banco.

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Breakdown of Los sábados voy al cajero automático que está frente al banco.

• estar: to be
• ir: to go
• al: to the

Questions & Answers about Los sábados voy al cajero automático que está frente al banco.

Why is it Los sábados and not something like En los sábados or just Sábados?

In Spanish, to say “on Saturdays” in a general, habitual sense, you normally use:

• el + day = on (that) day
• los + day (plural) = on (those days) / on X‑days in general

So:

• El sábado = on Saturday (usually one specific Saturday, or “this/next Saturday”)
• Los sábados = on Saturdays (every / generally on Saturdays)

You do not need a separate word for “on.” The article los does that job here.
En los sábados is not natural; it sounds like “in the Saturdays.”

Why is sábados plural here? Could I say El sábado voy al cajero automático?

Yes, but the meaning changes:

• Los sábados voy al cajero automático…
  → I go to the ATM on Saturdays (as a habit, regularly).

• El sábado voy al cajero automático…
  → I’m going to the ATM on Saturday (this coming Saturday / that specific Saturday).

So the plural sábados tells us it’s a regular, repeated action, not just a one‑time plan.

Why is only Los capitalized and not sábados?