The Pittsburgh map that we used is a 7.5 minute Digital Elevation Map, supplied by the USGS (United States Geological Survey) and can be freely distributed and available for download.

First, we took a panorama in the island by the 30th Street bridge, and had the system find the skyline:

The system's best estimate, processing the full map and with a plus/minus 15 degree tolerance, was the point (73, 346). The correct location was (71, 348), so the error was 85 meters. The posterior distribution (with a detail on the right) is below; the prior again was uniform.

Second, we took a panorama by the Waterworks Mall, and had the system find the skyline:

The system's best estimate, processing the full map and with a plus/minus 15 degree tolerance, was the point (306, 424). The correct location was (311, 423), so the error was 153 meters. The posterior distribution (with a detail on the right) is below; the prior again was uniform.

This work has been conducted at the Robotics Institute at the School of Computer Science, Carnegie Mellon University. It has been partially funded by NASA; Fabio Cozman has a scholarship from CNPq (Brazil). We thank these four organizations for all their support.