The Heron City shopping centre is an outlet shopping centre in Barcelona, it is not very big so do not expect a wide offer, it is more a local mall of the area and it is located in a neighbourhood that has no touristic value. 

If you are visiting Barcelona as a foreigner, I wouldn't recommend you to choose Heron City as the shopping centre to visit, there are plenty of shopping centres in Barcelona with a more central location and a wider offer of services. If on the contrary you live in the area, it might be a good choice as nearby shopping option in your neighbourhood. You can access to Heron City by public transport with metro L1 Fabra i Puig or L5 Virrei Amat.