The town is famous for its long beach (more than 5 km) and well known for being an affluent area, as the place of residence of many famous sportsmen, such as Lionel Messi,[4] Luis Suárez, Philippe Coutinho, or formerly Ronaldinho;[citation needed] and for being the city which inspired the creation of the character "El Neng de Castefa" who used to appear on the late night show called "BFN" hosted by the showman and presenter Andreu Buenafuente.

[6] In 2015, the eco-socialist Candela López of the ICV was elected mayor by a leftist government coalition.

The town is also the location of the Castelldefels and Nexus (sixth form college) campuses of the British School of Barcelona (BSB).

Transport links include two stations (Castelldefels and Platja de Castelldefels) on Renfe line R2 from Sant Vicenç de Calders to Maçanet-Massanes via Barcelona, bus routes to Barcelona (L94, L95, L97), Barcelona Airport (L99) and Sant Boi de Llobregat (L96), as well as an urban bus route connecting the rest of the town (CF1), the C-32 motorway and the C-31 and C-245 dual carriageways.

On 23 June 2010, 12 young people were killed, and 14 injured, when they were hit by an express train as they crossed the tracks in the railway station at Platja de Castelldefels, while on their way to a summer solstice bonfire party on the beach.