As it is captioned as 1897 it is likely to qualify under PD-old or similar. If you go to the source file you can download & then zoom to examine the writing in the bottom right (? Hotel * Westgate) It may then be able to trace the hotel which presumably distributed it & therefore get an exact date. You may also be able to zoom to see the detail of the posters displayed - although when I tried this the pixelation was too bad to read. Alternatively (again) why not just contact the Cleveland Pools web site & ask where they got it from?—  talk