Learn Hardcore Portuguese (Portugal): A marcação da consulta foi feita ontem pelo site do hospital. - The booking of the appointment was made yesterday through the hospital website.

Nouns ending in -ção are usually feminine: a marcação, a situação, a informação, a decisão, etc.
A marcação here means the booking / the scheduling (of the appointment).
Because it is a specific booking that both speakers know about, Portuguese uses the definite article a (the), not the indefinite uma (a).

So: a marcação = the booking; uma marcação = a booking.

What exactly does marcação da consulta mean? Why da and not just de?

Marcação da consulta literally means the booking of the appointment.

marcação de + [thing] is a very common pattern: marcação do voo (booking of the flight), marcação da mesa (booking of the table), etc.
Because consulta here is specific (a particular appointment previously mentioned or understood), Portuguese adds a definite article:
de + a consulta → da consulta.
If it were completely general, you could see marcação de consulta (booking of appointments, in general), for example in instructions or signs.

So marcação da consulta = the booking of the (specific) appointment.

Why consulta? Does it mean “consultation” or “appointment”?

In European Portuguese, consulta in this context is the normal word for a doctor’s appointment.

consulta can mean the consultation itself (the time with the doctor) and, by extension, the appointment.
In hospital/clinic contexts in Portugal, you will see consulta everywhere: marcar uma consulta, ter consulta às 10h, faltar à consulta, etc.
Using reunião would be wrong here; reunião is for meetings (work meetings, group meetings, etc.).

So you can think of marcação da consulta as “the booking of the (doctor’s) appointment.”

Why is it foi feita and not foi feito?

This is a passive construction, and in Portuguese the past participle agrees in gender and number with the subject.

Structure: foi feita = foi (was) + feita (made/done – feminine singular participle of fazer).
The subject is a marcação (feminine singular), so the participle must match: feita, not feito.
If the subject were masculine, you would say foi feito:
O pedido foi feito ontem. (The request was made yesterday.)
English doesn’t change the participle (was made stays the same), but Portuguese does in the passive voice.

So: A marcação … foi feita… (feminine) → feita.

Could we say A consulta foi marcada ontem pelo site do hospital instead? Is there a difference?

Yes, that sentence is correct, and the meaning is very close.

Original: A marcação da consulta foi feita ontem...
Focuses on the booking as a thing that was done.
Alternative: A consulta foi marcada ontem...
Focuses on the appointment itself being set.

Both are natural. The original uses a noun (marcação) plus the verb fazer; the alternative uses the verb marcar directly. In everyday speech, A consulta foi marcada ontem no site do hospital and Marquei a consulta ontem no site do hospital are very common.

Why use the passive foi feita instead of a more direct form like marquei a consulta ontem?

The passive foi feita sounds more formal and impersonal, which fits written contexts (emails, reports, administrative language).

A marcação da consulta foi feita ontem...
= The booking was made yesterday… (not stating who did it).
Marquei a consulta ontem...
= I booked the appointment yesterday. (clear first-person subject, more informal and direct).
You could also have an impersonal construction: A consulta marcou-se ontem pelo site do hospital, but that’s less common in this context.

So the choice is mostly about style and focus: passive → formal/impersonal; active → more direct and conversational.

Can ontem go in other places in the sentence? For example, Ontem a marcação da consulta foi feita...?

Yes, ontem (yesterday) is flexible in position, and several options are natural:

A marcação da consulta foi feita ontem pelo site do hospital. (very natural)
Ontem, a marcação da consulta foi feita pelo site do hospital. (also natural, with emphasis on yesterday)
A marcação da consulta ontem foi feita pelo site do hospital. (possible, but a bit heavier; more likely in speech with intonation helping)

What you generally wouldn’t say is A marcação da consulta foi ontem feita pelo site do hospital – that sounds very unnatural. The safest and most neutral option is exactly the original one: ...foi feita ontem pelo site....

What does pelo site mean exactly, and why not no site or através do site?

Pelo site is por + o site, and here it means “via / through the website”.

por + o → pelo (masculine singular)
por can express both means and agent in a passive structure. Here it’s mostly “by way of”:
foi feita pelo site do hospital = was made via the hospital’s website.
You could also say:
- foi feita no site do hospital = was made on the hospital’s website.
- foi feita através do site do hospital = was made through the hospital’s website.

All three are understandable. pelo site and no site are very common; através do site is a bit more formal.

What is do hospital exactly? Why not de hospital?

do is a contraction of de + o:

de + o hospital → do hospital
Literally: the hospital’s website = o site do hospital (the site of the hospital).
Using de hospital (without the article) would sound odd here. In standard Portuguese, specific institutions almost always take the article: o hospital, o banco, a escola, etc.

So pelo site do hospital is “via the hospital’s website,” with do = of the.

Portuguese seems to use a lot of definite articles: A marcação, da consulta, do hospital. Are they all really necessary?

Yes, in this sentence they are all natural and expected in European Portuguese.

A marcação – specific booking already known in the context.
da consulta (de + a consulta) – “of the appointment,” again a specific one.
do hospital (de + o hospital) – “of the hospital,” a specific hospital both people know.

Portuguese uses definite articles more than English, especially with:

abstract nouns (a saúde, a educação),
institutions (o hospital, a escola),
and when something is clearly identifiable from context.

Leaving them all out would sound ungrammatical or very strange in European Portuguese.

Is site just the English word “site”? Could we say sítio instead?

Site in this sentence is a borrowed word, but it is completely standard Portuguese for website.

In Portugal:
- site = website (almost always used in this sense),
- sítio = place/spot (physical or sometimes figurative, but not website in normal modern usage).
So o site do hospital is the normal, correct way to say the hospital’s website.

If you say o sítio do hospital, people will understand “the location of the hospital,” not its website.

Can we omit da consulta and just say A marcação foi feita ontem pelo site do hospital?

Yes, if the context already makes it clear that you’re talking about a medical appointment, you can drop da consulta.

A marcação foi feita ontem... – “The booking was made yesterday…”
In many real situations (everyone knows you’re talking about a hospital appointment), this is perfectly natural.
Keeping da consulta simply makes it explicit what kind of marcação it is, which is useful if there could be confusion (e.g. several different bookings in the conversation).