This is a bonus cache for the Adventure Lab called Albany History: Dogs on Trains. It can be found via the app or using the link https://adventurelab.page.link/Mc8b . Some of the locations of that Adeventure Lab will include a numerical value for the letters in the coordinates below:
N 42 AB.CDE
W 73 FG.HIJ
When you solve these coordinates, you will discover they lead to a sidewalk where you can look (then reach) inside to find the prize.
Note: for previous solvers of the Adventure Lab, your gallery should have updated descriptions that include the coordinate code.