Hi, At least two days as there is so much to explore
1 day will do but 2 days are better.
if you just want to see the main attractions it could be in just 24 hours, i always like to stay more to feel the city spirit and Cordoba is a beautiful city so i would recommend 2 or 3 days and wonder around its beautiful streets and the tasty Gastronomy
You can do the high points in 24 hours. The major thing to see is the Mezquita, the big mosque that was turned into a Catholic cathedral. If you get there the day before, walk around the Jewish quarter and see the old synagogue, then in the evening have a good dinner and stroll along the river bank. The old Roman bridge isn't. It's a reconstruction along with the pseudo temple, but it's very pleasant. The old town is quite small so it is easy to get around. I'm not sure if you can get tickets to the mosque/cathedral in advance; our guide got ours.
I would spend 2 days
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