The term 壮观 is deeply woven into the Chinese appreciation for both nature and human achievement. China's geography is filled with vast, awe-inspiring landscapes—from the towering Himalayas to the karst mountains of Guilin and the mighty Yangtze River. Describing these places as 壮观 is a common expression of national pride and reverence for nature. Similarly, China's long history is marked by monumental engineering feats, such as the Great Wall, the Terracotta Army, and the Grand Canal. These are not just historical sites; they are symbols of collective effort and endurance. Calling them 壮观 acknowledges their immense scale and the incredible human power required to create them. To compare this with a Western concept, think of the word “sublime” as it was used in 18th-century art and philosophy. The sublime referred to a beauty so vast and powerful that it was almost frightening, inspiring awe and a sense of one's own smallness. 壮观 carries a similar feeling but is used more commonly in everyday language. It's less about fear and more about sheer, breathtaking impressiveness. While an American might say the Grand Canyon is “awesome” or “incredible,” the Chinese word 壮观 specifically pinpoints its visual magnificence and grand scale.
壮观 is a common and useful word in modern Mandarin, appropriate in both formal and informal contexts when the subject is suitably grand.