Here are two original photos of Chicago's famed West Side Grounds, the ballpark the Cubs called home before moving to Weeghman (later Wrigley) Field in 1916. According to the seller, these pics date from the 1901-1904 period, which is a pretty good estimate given that there are no dugouts and we know from later photos that dugouts were in place by 1905. Chicago played at a .651 clip here in the period of 1902-1910 (not to mention .634 on the road).
*An on-site plaque commemorating the old ballpark was dedicated in 2008.
*The gigantic billboard running across the length of right field reads "Tribune always has the best baseball news." It would later read "The Tribune always makes a hit with its sporting news" and then "Baseball stories by Dryden and Sy in the Tribune this year" followed by "Chicago Tribune, Worlds Champion of the Sporting News."
*Yes, that is the clubhouse in play in center field. It was 560 feet from home plate.
*Note the fans on the tops of buildings beyond the clubhouse (see detail below). They are about 2/10 of a mile from home plate.