Were going on vacation to Spain and would like to know if its permissible to watch a bullfight.
My apologies that I didn’t get to answer you for a while.
It is not permitted to go to watch bullfights. The reason being because our torah teaches us to be compassionate even to animals, as we have a specific mitzvah not to pain an animal and even if an animal it carrying a heavy oad we have to help the owner unload it so the animal won‘t be in pain. A bull fight is the exact opposite of this. The bull is starved beforehand to make his hungry and mad, he is poked with spears to get him even more mad. Therefore it not permitted to do this to the animal, and by attending such a fight we are supporting those who are doing forbidden things.
Yichave Daat 3-66. See Tractate Avoda Zara 16a Rashi D:H Itztadion.