Green Monster

The Green Monster is a popular nickname for the 37'2" (11.33 m) high left field wall at Fenway Park, home to the Boston Red Sox baseball team. The wall is only 310 feet from home plate and is a popular target for right-handed hitters.

The wall was part of the original ballpark construction of 1912. It is made of wood and was covered in tin and concrete in 1934. It was then covered with hard plastic in 1976. A manual scoreboard is set into the wall. Despite the name, the Green Monster was not painted green until 1947; before that, it was covered with advertisements. The Monster designation is relatively new. For most of its history it was simply called "The Wall."

The Green Monster is the highest among the walls in current Major League Baseball fields, and is the second highest among all professional baseball fields (including minor leagues), falling approximately 6 inches short of the left field wall at the PeoplesBank Park in York, Pennsylvania.

Ballparks occupied by professional baseball teams have often featured high fences to hide the field from external viewers, particularly behind open areas of the outfield where bleacher seating is low-lying or non-existent. The wall might also reduce the number of "cheap" home runs due to the barrier's relatively close distance to home plate. Fenway's wall serves both purposes. Past ballparks of Fenway's era or even later which featured high fences in-play included Baker Bowl, Washington Park, Ebbets Field, League Park, Griffith Stadium, Shibe Park, and more recently, Los Angeles Memorial Coliseum. Fenway is the last of the exceptionally high-walled major league ballparks. Relatively high walls in modern ballparks have been constructed for their novelty rather than by necessity, as Fenway's wall had been.

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