Cheonggyecheon at Night — Seoul Binaural Walk

Cheonggyecheon is a stream that was buried under an elevated motorway in the 1970s and dug back out in 2005, dropping a five-mile water course several metres below the traffic through the middle of Seoul. Acoustically that trench is the whole point: the city is right there above you, but the running water and the sunken walls take the top off it, so you get a muffled version of downtown with a stream in the foreground.

Recorded binaurally, so on headphones the traffic sits above and behind while the water stays low and close. It is the most unusual entry in the city collection here — every other walk puts you in the street, and this one puts you underneath it. Good for focus precisely because of that layering: busy enough to mask a room, distant enough to ignore.