Fort Frederick is the site of an eighteenth century English fort located in the community of Placentia, NL. Fort Frederick has been designated a municipal heritage site by the Town of Placentia due to its historic value.

It was erected on the town side of Placentia in 1717 to protect English interests in the seasonal fishery. However, as a permanent population on the island grew, the role of the military increasingly became one of maintaining public order and suppressing civil unrest. England withdrew its military garrisons from Newfoundland in 1870, thus paving the way for the establishment of a civilian police force.

Archaeological work on the Fort Frederick site in 2000-2002 revealed a large collection of artifacts. Archaeologists uncovered barrel staves, cannon and musket balls, flints, Dutch tobacco pipes, pieces of pottery and tableware and coins. One coin in particular dates to 1630, confirming that Placentia was occupied by people before the French colony of Plaisance was established in 1660.