Apart from Sevilla where you'll find the most popular Holly Week, other popular destinations are Zamora and Valladolid.

CathyM writes:
The Botafumeiro is an incense censer that is said to have been used because the pilgrims who slept in the cloister emitted some foul odors. In normal years, the Botafumiero is only used on Church feast days (Palm Sunday, Easter, Pentecost, etc.). In año Santo you can see it in action more often (Saturday's Pilgrims' Mass, for example).

Trivia: What are the people called who pull the ropes that guide the Botafumeiro??

I have travelled to Madrid several times for Holy Week: Flights are usually very crowded with school children making a Spring Break trip (the Mother of all slumber parties is what I called it). How it will be after 9/11 is really anyone's guess. Palm/Passion Sunday (Mar 24) you may be all right going there; but Friday and Saturday probably wouldn't be very good for stand-by fliers. Even Easter Sunday might be a problem coming back.
Lots of luck! You'll need it.

Answer to my Trivia question: Tiraboleros!

[ 01-15-2002: Message edited by: Eddie ]

It seems that the Boutafumeiro makes its appearance only during special events.

However, some years ago my cousin visited the cathedral with a group of people the Botafumeiro was "magically" turned on after they paid 25000 pesetas (150 euros).

Rafael writes:
We went from Madrid to Alicante & back once for Holy Week and the Train (Talgo) was as crowded as I have ever seen. Book your bus or train tickets a day or more in advance and you shouldn't have any problem. When we day-tripped to Sevilla for Good Friday we didn't have any problem with reservations & tickets for the 0830 AVE Thursday (i.e., the day before).
Don't expect to find lodging in Sevilla (unless you're already booked) Wed, 3/27 thru Fri, 3/29.

Thanks for the SS recommendations, Antonio. Let me second the motion on Valladolid. Having only a video of Sevilla's to compare to, (which isn't fair), I will say that Valladolid's Semana Santa procession is impressive. The ENTIRE city seems to be in the main square, too. [Note to self: Go to Valladolid during Semana Santa...wait for procession to start, leave main square, and LOOT TOWN.]

Zamora may be even better as it's fame is known and it is a much smaller town than Valladolid. I've also been in Avilés for Semana Santa, and they had a good procession.