Riga's National Library, often called the Castle of Light, is the landmark building of the city's newer west bank. Built between 2008 and 2013, it rises in a sharp glass form that deliberately contrasts with the old town skyline across the Daugava.
The building is worth seeing even if you do not need the library itself. Cross the river for the best approach, then look back toward the old city from the west bank for one of Riga's strongest modern views.