Another great activity to do on a rainy afternoon in El Retiro Park is to explore the gardens surrounding the Palacio de Cristal. These gardens are filled with lush vegetation, colorful flowers, and winding paths. Grab an umbrella and take a leisurely stroll, admiring the beauty of nature in the rain. The raindrops will add a magical touch to the scenery, making it even more enchanting. Don't forget to bring your camera to capture the vibrant colors and the rain-kissed foliage.