The Basilica de Santa María stands at the heart of Portugalete's old town, a late-Gothic church built between the 15th and 16th centuries on a site where a chapel has stood since the town's founding in the 14th century. The facade, worn smooth by salt wind off the estuary, faces a small square with benches and good views down to the waterfront. The interior is plain by Spanish standards — three naves, pointed arches, a retable over the main altar — but has the quiet dignity of a working parish church rather than a tourist monument.
The church's position at the top of the steep old town makes it a natural endpoint for a walk up from the riverfront. From the small square in front of the facade you can look back down across the rooftops toward the Vizcaya Bridge and the estuary.