Q: What are my options night transport leaving Barcelona city centre at 04:00 on a Sunday morning? Thank you for your help.
A: You have 2 main options a) Night bus N17 or b) Taxi.
You can catch the Night Bus N17 that operates daily from 21:55 - 04:45 (at T1 Barcelona Airport) and 23:00 - 05:00 (at Plaza catalunya) and runs every 20 minutes. The bus operates from Plaza Espanya which is a road near Plaça Catalunya to Barcelona airport and Vice Versa. Price for the ticket is €2.00 . The journey time is approximately 30 minutes. The N17 also has a stop at Plaça Espanya. The N17 bus travels both to T1 and T2.
Alternatively you can take a taxi and the price will be around €25.00 to Terminal 2 and €30.00 to Terminal 1.