Kim, by Rudyard Kipling
I made my daughter read Kim as part of her history this year (which features a whole lot of British Empire material), and once she was done I read it too. I avoided Kim when I was a teen myself, mostly because it had the world's most boring cover, all yellow and dusty-looking. (If you come from Bakersfield, a drought-stricken landscape book cover does not look exotic or attractive.) If I'd known it was about India and spying and lamas, I would have snapped it up--well, maybe, since I also had an aversion to historical fiction.
Kim's father was an Irish soldier, but both mother and father died soon after his birth, and so Kim has grown up on the streets of Lahore, ignorant of his parentage. He becomes a sort of apprentice and caretaker of a wandering Buddhist monk, a very learned lama--and he also undertakes some secret message-passing on the road. Once Kim is noticed by a British officer, he is brought into the "Great Game" of espionage and competition with the Russians, but his priority is his relationship with his beloved lama.
It's kind of an odd plot actually, but it works. Kipling wants to show you what he loved--the land and people of India--so he puts Kim on the road to see as much as possible. And yes, it's from the perspective of a guy who truly believed in the British Empire. But most of it is about the wonders of India.