Logan House
Sadly, the plaque is located between the wall for a parking garage for the Altoona Amtrak station, and the chain link fence for the parking lot of the Altoona USPS building. Coordinates here:
http://explorepahistory.com/hmarker.php?markerId=1-A-1CF
This blurb has been supplemented by , where you can find the following:
“Next to the station was the famed Logan House, a hotel funded by the PRR and completed in 1853. With a deep and inviting verandah stretching more than 200 feet along the tracks, the hotel featured hot running water and gas lighting. The platform area and tracks were covered by a large cast iron train shed that protected travelers from inclement weather. Before dining cars were standard, passengers had to detrain to take meals and the main dining room of the Logan House buzzed with activity. Altoona was a natural stop since it was also a division point where train crews had to be exchanged.
At the center of an extensive rail network, Altoona was chosen to host the Conference of Northern War Governors in September 1862. Convened at the Logan House by Pennsylvania Governor Andrew Curtin, the gathering of leaders discussed the events of the Civil War and publicly endorsed the efforts of President Lincoln, including his plan to emancipate the slaves within the Confederacy. The hotel stayed in operation until 1927 when the PRR sold it to the federal government, which later tore it down to build a new post office.”