First time to Spain Itinerary (10-12 days)

Sorry, but your itinerary sounds far (far!) too hectic to me already... 12 days visiting 6 cities?... you must be joking! :))) Mind me, but 12 days should warrant a couple of cities tops plus maybe a couple of escapades around them. Note that visiting any of these cities (actually, just scratching their surfaces!) would require at least two or three days each, for the smaller, and five to seven for the bigger. These not counting escapades, and each city is in a different region with plenty to choose from. Just sayin'.

IMHO, you should focus on two regions max.... and seeing your choices we're talking about choosing among Catalonia, Castille, and Andalucia.

Enric is right. In 10-12 days, choose two of the following three:

Madrid and around (Toldeo, Segovia, etc)
Barcelona and around (Girona, Sitges, etc)
Andalucia (Seville, Granada, Cordoba).

While these are the most common destinations for a first trip to Spain, if you're drawn somewhere else, that's fine too. Just realize you will then have to drop one of the other areas.

Spain is a larger country than it seems at first, and getting from place to place quickly can be easy or hard, depending on which places you're trying to connect. Do investigate transit links before making any firm commitments. And be open - depending on what you're trying to connect, it may be best by train, bus, domestic flight, or car.

Have you already booked flights from the US (assuming that's where you're coming from)? If not, do look into "open jaw" (multi city) flights - say, into Granada and out of Barcelona. To find these flights, use the "multi city" or "multiple destinations" function of Kayak, Google Flights, Iberia, etc. On a short trip, these kinds of flights can save a lot of time and money in not backtracking, so they're worth the potential "extra cost" up front (and there may not be any compared to a simple roundtrip).

On the other hand, if you already have booked flights, let us know what they are.

How temperature sensitive are you? If you don't mind high heat, you'll be fine in the places you listed. If you do, you'll want to check carefully before planning. Unfortunately, I can't get my usual website (Wunderground) to work right now, but try to find actual historical temperatures for your travel dates in 2017, 2016, etc. This is much more useful than "average" temperatures.

For 12 days I would recommend 3 cities at the most since you will loose 1/2 day eveytime you move.
Madrid, Sevilla and Granada (for example) have a lot to offer.
You can spend a night in Toledo and do day trips to Jerez (or another white town) and Cordoba from Sevilla.
Have fun!

Not sure of your home airport, but one thing I've done for France and now Spain, is focus on a region and try to make sure I'm covering everything I want in that region. If necessary, I spend very little time in my "airport city". From Minnesota, our selection of European cities that we can get to at a decent price in some kind of time efficient manor is limited. I anticipate coming to Spain at least three times. This time my focus is on Andalusia. My trip length is 12-13 days. Every time I come to Spain, I'll probably be flying into Madrid so I don't need to see much of Madrid now. I'm spending my time in Sevilla, Granada and Cordoba and Toledo and then just one night in Madrid since I know that I'll cover Madrid on future trips. I travel at a pretty fast clip, and pack a lot in a day. Even for me, your trip length and the number of cities you have in mind are too much. I would suggest you cover either Barcelona/Costa Brava/Catalunya OR Andalusia/Toledo/ and a day in Madrid if that is your "airport" city.

It would be nice if you could fly open-jaw between Madrid and Barcelona. Otherwise, flying in and out of the same airport isn't that big of a deal, given the ease of train connections.

With your limited time, I would limit the trip to Madrid and Barcelona, with day trips to other destinations.

When we were in Spain in October 2017, we used Spanish Trails for one day trip from Madrid (Segovia) and three day trips from Barcelona (Priorat Wine Country, Tarragona and Girona/Costa Brava). Truthfully, I couldn't pick a favorite.

http://spanish-trails.com/mad/about-spanish-trails/

http://spanish-trails.com/day-trips-tours/gourmet-food-wine-tours/

Harold gave you some great advice. Spain is a large country and impossible to see even the key places in 10-12 days.

Plan and coming back and visit Portugal as well.

Day
1. ARRIVE Barcelona (3N)
2. Barcelona
3. Barcelona
4. Fly to Granada (2N)
5. Visit the Alhambra
6. Train to Seville (3N)
7. Seville
8. Seville
9. Early train to Cordoba for the Mezquita, then late train to Madrid (3N)
10. Madrid
11. Day to Toledo (or Segovia)
12. DEPART Madrid

David always has some of the best, most concise itineraries around here.

Hi Everyone- I had to cut the trip a bit short due to work restraints. I was thinking of the following schedule:

1: Madrid (Fly from London to MAD)
2: Madrid
3: Toledo Day Trip; Sleep in Madrid (Fly from Madrid to Seville)
4: Seville
5: Seville w/Granada day-trip Maybe? (Fly from Seville to BCN)
6: Barcelona
7: Barcelona
8: Barcelona (Fly from BCN to JFK AT 10 pm)

It may be possible to add one more day. We are coming from a week in London, so the jet-lag won't be a huge issue. I understand we won't cover each city nearly in depth but would love to give our son an overview of Spain's highlights.

I'm confused about how many days you have, but train will be much faster than flying between Madrid and Seville by the time you factor in the time needed to get to and from the airports, etc.

I think Granada is too far from Seville to be a reasonable day-trip. I wouldn't go if I couldn't fit in the full Alhambra experience. I'd add that day to Barcelona, but you could instead do a day-trip to Cordoba.

Seville back to Barcelona is probably a smidgen faster by air, but you're likelier to have delays when flying.

If you can add an extra day, how many nights would that give you in Spain? Perhaps that would make the Alhambra viable, but you really need to spend the night in Granada to pull that off.

With reduced time something definitely has to give. Leave Seville and Andalusia for a future trip that avoids the heat of August.

1: Fly from London to Madrid (4 nights)
2: Madrid
3: Toledo Day Trip
4: Segovia Day Trip
5: Train to Barcelona (3 nights)
6: Barcelona
7: Barcelona
8: Fly from Barcelona to JFK at 10pm

Three seperate comments

a) I'm not clear about your plan. On day 3 do you sleep in Madrid and fly to Sevilla on day 4? That gives even less time in Sevilla. Similar comment on day 5. But if this is your preferred itinerary, then you should definitely consider Madrid to Sevilla by railway, not a flight. And rather than doing a day trip from Sevilla to Granada, go one way and then fly from Granada to Barcelona

b) More significantly, I think your plan is too whirlwind and suggest you cut to two main bases. With the heat and crowds you will want to slow down a bit. For a general overview and some contrasts, I suggest flying from London to Andalucia (several options available, but probably getting dear now given how popular the routes are). Spend four days in Sevilla, with Cordoba day-trip, then a night in Granada to see the Alhambra (if tickets still available), then fly to Barcelona for three days.

c) If this is August 2018, then don't spend much longer procrastinating, whatever you eventually decide. This is peak tourism and everywhere is busy and some accommodation, travel options, etc. already sold out.

PS Madrid in August isnt a bad idea. It's hot, but usually not so humid, some Madrileño/a leave for their own holidays and the traffic is better. On the other hand Madrid is great if you like art galleries, not as interesting as southern Spain if you don't.