Lioness Rampant by Tamora Pierce

In this fantasy novel, the final installment of a quartet, a young female warrior completes her transformation from a stubborn apprentice to a powerful and confident knight. She embarks on a quest to recover a legendary artifact that could save her kingdom from impending danger. Alongside her loyal companions, including a prince, a mage, and other magical beings, she faces a series of challenges that test her skills, courage, and determination. As political intrigue and battles loom, the heroine must confront her own personal demons and make difficult choices that will shape her destiny and the future of the realm she is sworn to protect. The 12174th greatest book of all time