Breakdown of Lo que estaba buscando era la oficina de la alcaldía.
ser
to be
de
from / of
estar
to be (location/state)
la oficina
office
Questions & Answers about Lo que estaba buscando era la oficina de la alcaldía.
Why use lo que to start this sentence instead of just saying Estaba buscando la oficina...?
This is a pseudo-cleft sentence, a structure used to emphasize a specific part of the sentence. By starting with lo que (meaning "what" or "that which"), you build a little anticipation and put heavy focus on the object you were seeking. It works exactly like saying "What I was looking for was..." in English instead of a plain "I was looking for...".
Why is it era and not fue?
We use the imperfect tense era because both halves of the sentence are describing ongoing, background situations in the past. You were in the middle of a search (estaba buscando), and the identity of the place you wanted is a continuous fact, not a sudden completed event. When linking these ongoing past states with lo que, era is the natural choice.
Why is there no Spanish word for "for" after buscando?
I've learned ayuntamiento for city hall before. Is alcaldía different?