Picea abies outside of its native range, and one of the most economically important coniferous species in Europe. It is used as an ornamental tree in parks and gardens. It is also widely planted for use as a Christmas tree. Every Christmas, the Norwegian capital city, Oslo, provides the cities of London (the Trafalgar Square Christmas tree), Edinburgh and Washington D.C. with a Norway spruce, which is placed at the most central square of each city. This is mainly a sign of gratitude for the aid these countries gave during the Second World War. In North America, Norway spruce is widely planted,
Trafalgar Square construction started, impeding its progress. The square was to be named for William IV commemorating his ascent to the throne in 1830. Around 1835, it was decided that the square would be named after the Battle of Trafalgar as suggested by architect George Ledwell Taylor, commemorating Nelson's victory over the French and Spanish in 1805 during the Napoleonic Wars. After the clearance, development progressed slowly. The National Gallery was built on the north side between 1832 and 1838 to a design by William Wilkins, and in 1837 the Treasury approved Wilkins' plan for the laying out of the square, but