Adarlan is a fictional kingdom in the popular book series "Throne of Glass" by Sarah J. Maas. It is known for its powerful military and strict social hierarchy, where the ruling class maintains control over the common people. The kingdom is characterized by its harsh laws and a strong emphasis on loyalty to the crown. The capital city of Adarlan is Rifthold, a bustling metropolis filled with opulence and danger. The kingdom is also home to various magical creatures and has a complex history involving wars and conquests. Throughout the series, Adarlan plays a significant role in the development of key characters and their journeys.