Brandon of the Engineers by Harold Bindloss

The sure-footed mules, braced hard against the weight of the carriage, slid down a steep descent across slippery stones when Clare, who wondered what would happen if the worn-out harness broke, rode into Adexe. Gleaming white houses rose one above another among feathery palms, with a broad streak of darker green in their midst to mark the shady alameda. Behind, the dark range towered against the sky; in front lay a foam-fringed beach and the vast blue sweep of dazzling sea. Music came up through the languid murmur of the surf, and the steep streets were filled with people whose clothes made patches of brilliant color. The carriage jolted safely down the hill, and Clare looked about with interest as they turned into the central plaza, where the driver stopped.

"It's a picturesque little town and I'm glad you brought me," she said. "But what does the fiesta they're holding celebrate?"