I am planning a trip in May to Madrid and then to Barcelona. Thinking of 3 nights in Madrid(too many?) and 4 days/nights in Barcelona. Should we include Seville - and how do you get there from Madrid and from there to Barcelona?
thanks for any info!

I'd do 4 in Madrid and 3 in Barcelona, but then I liked Madrid better than Barcelona and am probably in the minority of people who say so. I think you need at least 3 nights in both places ... there are tons of museums in Madrid, for example, that merit at least a full day if not 2 doing just that (unless, of course, you aren't a museum person) plus a great palace and cathedral.

I would suggest 4 nights in Madrid also, and only 3 nights in Barcelona. On the outskirts of Madrid there are several small historic towns that are each worth a day trip to visit, e.g. Avila, Toledo, Segovia.

I agree with 4 nights in Madrid. To get to BCN, you can take the train (about 5 hours) or fly (Vueling has very good fares).

May 15 is San Isidro, one of Madrid's Patron Saints (St. Isidore the Worker). There's a lot going on in Madrid then (i.e., daily bullfights, concerts, etc.) so you might want to stay a bit longer in Madrid (w/ Toledo, Segovia, Escorial).

Will you be flying home from Madrid or Barcelona? You'll want to minimize any backtracking ...

Sevilla is nice, but the Feria de abril will have concluded and the Feria del Campo won't be until the end of May, so with just 7-nights, Madrid & Barcelona should be pretty much a full plate.

I just came back from Spain and yr planning seems sensible to me. You'd need at least 2 days in Seville (which is 3hrs away by train) , and that means you would not enjoy the other cities as you should.....

For traveling direct Madrid to Barcelona I used the night train and recommend it. Seville seems to be in the opposite direction.