Read this passage:
Sarah always looked forward to her weekends at the lake. The calm, serene water made her feel at peace, and the gentle breeze was a welcome change from the bustling city. One evening, as the sun began to set, she noticed the sky turn a brilliant shade of orange, painting everything in a golden glow. She felt a deep reverence for nature.
Based on the passage, what could be a synonym for the word "serene"?