This is the ambience of a washroom near the parking lot of a small business building. You can hear the hum of the air-conditioner and the distant chirping of a large flock of birds. I recorded this with my lenovo laptop's built-in microphone.
Atmo of the portico of the national gallery in london. Lots of visitors from all over the world pass by, talking loudly. Recorded with a zoom h-2, mics set to 90° dispersion.