The Heydar Mosque in Baku, Azerbaijan, is a modern architectural marvel showcasing intricate Islamic design. It is generally accessible to visitors, but modest attire is required (headscarves and long clothing are often available at the entrance). Exploring the mosque can be done solo to appreciate the details at your own pace, or guided tours might be available for deeper insights into its history and significance. There are no specific seasonal restrictions, but it's advisable to check prayer times to avoid visiting during services. A typical visit lasts around 1-2 hours. Admission is usually free, but donations are welcome. Photography is permitted, but be mindful and respectful of worshippers.