Open-air lobbies, also known as atria, are enclosed spaces that are open to the outside environment. They are typically found in large buildings and are designed to provide natural light and ventilation. Atria are often used as gathering places for people to meet and socialize. They can also be used to provide a visual connection between different parts of a building. Open-air lobbies are becoming increasingly popular in modern architecture due to their ability to create a pleasant and inviting atmosphere.