Pre-Barcelona

A planned trip to Barcelona is on the agenda at the moment.
Maybe I can use this blog to get some more suggestions/hints on visiting this famous city.

Feel free to post comments (tips, hints and suggestions).

As yet I have these interests (which may or may not be seen/accomplished):

La Sagrada Familia
The Dalí Museum in Figueres
Tibidabo - hill with a glass lift that goes 115m (377ft) up
Costa Brava - the sea coast
Hiking - somewhere (still dont know where)
Barri Gòtic with its Catedrál - centre of old Barcelona
Gràcia -quarters with artists and intellectuals
La Pedrera - the quarry house of stone
Museu Picasso

....suggestions?