It sits above railroad tracks.
The strange listening spot is part of an elevated pedestrian plaza, not a patch of sidewalk at the posted address.
The bridge once carried cars.
The original Boston Avenue crossing dates to the 1930s and served vehicles before the later pedestrian reconstruction.
The center marker is about 30 inches wide.
Tulsa City-County Library describes the worn concrete center as much smaller than many first-time visitors expect.
Thirteen rows of brick make the larger circle.
Together they form a ring approximately eight feet across around the small central marker.
The echo seems to be a happy accident.
The acoustic behavior is associated with the reconstructed plaza's geometry, not a documented plan for an engineered trick.
Outside listeners are not struck mute.
They can hear the sound. They simply receive a different mix of direct and reflected energy than the person near the center.
Artificial Cloud is about 72.5 feet tall.
The public artwork dwarfs the acoustic marker and radically changes the plaza's silhouette.
Rust belongs to the artwork.
Robert Haozous intended Artificial Cloud to weather as part of its material and conceptual life.
Engineers studied the echo.
Redevelopment planning included acoustic expertise so the critical conditions could be understood and protected.
The inner walls are staying.
City statements say the concrete walls responsible for the phenomenon will be preserved through rehabilitation.
Old illuminated brick artwork is leaving.
The redevelopment plans remove Trace while preserving Artificial Cloud and the core acoustic setting.
Tulsa King brought another audience.
The location appeared in the series, and an episode title made the landmark easier for viewers to discover.
Cosmology gives Tulsa a loophole.
An expanding universe has no ordinary privileged center. So Tulsa is not literally it—but neither is anywhere else.