If you're in the northern part of the city and you see a massive group of runners at night, don't worry, it's only the annual Cursa de Bombers (Firefighters' Run), a 10k sponsored by the ubiquitous Nike. The race leaves Plaça Espanya via Av. Reina Cristina and ends at Selva de Mar. The route along the way goes along Paral·lel, Pg. Colom, Pg. Picasso, Sardenya, Marina, Av. Meridiana and Av. Diagonal. If you're interested in
signing up, fill in the form on the website (places available until they've reached capacity). (Note that the registration form is available in Catalan and Spanish only.)