Spain Itinerary for October - arriving from Paris by train

Looks great overall. I’m not sure about a day trip from Sevilla to Granada though. I’m sure it’s possible and people do it, I just avoid long day trips so cannot say.
You could consider staying in Granada, but you’ll have no trouble filling five days in Sevilla.
You could also consider skipping Barcelona to give more time in the other places.

I've taken the train between Barcelona and Paris (going north). It's a nice enough ride, but it's a pretty long trip that way (figure 6-7 hours at best). Flights are dirt cheap, and under 2 hours. Even if you factor in time lost around the airports, the flight may be a better option in some cases, although it might be a close call (check timing and costs carefully on the date you would travel).

What interests you most about Spain?

With only 14 nights, I think you may be over stretching trying to visit the 5 top cities in Spain in 3 different regions, you'll be missing out on a lot. My inclination would be to save southern Spain for when you can do it justice, and not just day trip to the great cities of Granada and Cordoba, and Toledo definitely deserves an overnight too. At least I'd probably add 1-2 more nights to Barcelona if you can, and that's without any added day trips from Barcelona.

Everyone's travel style is different, but my suggestion would be:

Barcelona (5 nights) + day trip to Girona or Tarragona
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Zaragoza (2 nights)
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Madrid (4 nights) + day trip to Segovia or Salamanca
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Toledo (2 nights)
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Madrid (1 night)

I'd argue that the proposed itinerary doesn't have time for a day trip to Toledo if you're only spending three nights in Madrid. Three nights is 2 full days and 2 half/travel days. You could barely fit "check-list" tourism of the city itself into that time.

We are heading to Sevilla soon for six nights and are planning day trips to Cadiz and Carmona. We will have already been to Cordoba and Granada before Sevilla.

Update: Based on all of your suggestions and useful tips, I’ve decided to wait until next year and take more time to leisurely explore Spain. I don’t think 2 weeks is enough to see everything that I now have on my list. Someone mentioned why not just stay in France and I think that’s a good idea. I’ve been to France many times but there will always be places that I have not seen. Since I’m retired I like to spend 4 weeks in Europe twice a year. Spain will be one of those 4 weeks. Thanks again for your input and awesome suggestions.

Aussie, did you take a train to those places?

If it were me, I would fly to Barcelona for five nights, fly to Seville for 4 nights, fast train to Madrid for 5 nights and just do a day trip to Toledo. Fly home from Madrid.

The two flights should save you time. And you will not have to split your stay in Madrid or double back to Madrid by train, if you were to go to Madrid before going to Seville.

Seville to Cadiz is by train; Seville to Carmona is by bus. Seville has two bus stations; be sure you know which one the Carmona bus uses. (I don't remember,)

Seville to Cadiz is by train; Seville to Carmona is by bus. Seville has two bus stations; be sure you know which one the Carmona bus uses. (I don't remember,)

Thanks. We will check that. We don't get to Seville until early March.