7 days in Spain

7 days solo keep it at Seville to Toledo to Madrid. They are on the same train line.
I recommend searching Booking.com for hotels. You can filter by price range.
You can take a guide book out of the public library and read between now and then to discover what you are interested in seeing or doing.

Toledo's actually on a dead-end rail line that connects only to Madrid. So you'd need to go to Madrid and change trains there in order to reach Toledo from Seville. Definitely worth it. Toledo is a wonderful city.

Understand, though, that it may be pretty cool in Madrid and Toledo in January. It will probably be much warmer in Andalucía; the average January high temperature in Seville is 14F warmer than in Madrid.

Akeen,

You could also visit Córdoba, for a few hours, en-route to Madrid. You may store your luggage at the bus station which is conveniently located across the street from the train station.

I had 7 days in March and split it evenly between Seville and Madrid with a travel day in between and a day trip from each city. I chose Toledo from Madrid and Cordoba from Seville, although you could easily visit Cordoba as a stop off for part of the day on your way between Seville and Madrid, which would give you more time in Seville.

Without knowing your interests, I can only tell you what I liked most. And without knowing your budget, my hotel recommendations may not be useful. Anyway, here goes.

Sevilla. Top sights - the Alcazar, the cathedral (especially Columbus's tomb, the exterior and the tower), the Plaza de Espana, the Palacio de las Duenas, a performance at La Casa del Flamenco. Hotel: Amadeus - beautifully decorated, very comfy beds, modern bathrooms, great staff, and excellent location.

Cordoba. My favorite Spanish city, worth a couple of nights. I stay at the budget Don Paula, great location, clean, comfortable. The Mezquita is the best sight in Spain after the Alhambra. But there's more - a wonderfully well-preserved medieval quarter (the Juderia), horse shows at the Royal Stables (check the dates, only 2-3 per week), several small, interesting museums - if you are planning to spend a couple of days here and are interested, PM me and I'll give you more details.

Madrid. Hotel Europa is a great location. I've stayed on both my visits as have others on this forum, RS tours use the hotel too. The art museums are the big draw - Prado, Thyssen and Reina Sofia. That's great if you love European painting. If not, 2 full days in Madrid may be a lot, especially in January when the parks and gardens won't be much to see. It's convenient for day trips to Segovia and Toledo, but check the weather before you go. They are higher elevations and may get snow. Toledo is very hilly (like San Francisco hilly), so walking in snow might be too challenging. I enjoyed the Navy Museum. The palace is one of the best in Europe.

Either
1. Arrive Seville (4)
2. Seville
3. Day to Cordoba
4. Seville / Day to Jerez
5. Train to Madrid (3)
6. Madrid
7. Day to Toledo
8. Depart Madrid

Or
1. Arrive Seville (3)
2. Seville
3. Day to Cordoba
4. Train to Madrid (4)
5. Madrid
6. Day to Toledo
7. Madrid / Day to Segovia
8. Depart Madrid

Last time in Sevilla I stayed at hotel Amadeus. It’s near the cathedral. In Madrid, hotel Europa because of its location. In Toledo I stay at hotel Maria Cristina. It’s only a few minutes walk from the main gate to the old town and train station.

I have to say that I disagree with the idea of spending time in Alicante on a week-long January trip to Spain.

I agree Ann. I'm thinking that reply was from a bot. GRRRRR