Search inside the imagery. On every corridor we have read, each scene is described frame by frame: objects, signage, surfaces, water, people. Each of those observations is searchable. Try “wooden bridge”, “stop sign”, “boat launch”, or pan the map and search the area.
Searching 81 corridors in 25 states · 36,006 scenes read so far. Reading rolls out corridor by corridor across 915,777 public 360° scenes, so a place that has not been read yet comes back empty here. That is coverage, not a failed search.