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Keywords from Image Description:
castalia castalia ohio castaliaohio blue hole bluehole the blue hole thebluehole pond ponds tourist sites touristsites geo. h. tremper geohtremper c.t. artcolortone ctartcolortone curteichchicago curteichchicago curteich date unknown dateunknown linen postcard postcards divided back dividedback white border whiteborder white border