The sites that were finally chosen for most of the shooting of the scenes of Garret's hometown were Northport and Popham Beach, Maine. Over $250,000 of renovations were done to the seasonal home in Popham that became Garret's house, including the addition of the room which held Catherine's artwork and the adjacent living room with fireplace (faux). At the end of filming the owner of the house demanded that it be returned to its original state costing the production company nearly as much to undo.

This is the 1st film adaptation from a Nicholas Sparks novel.

The producers originally planned to film on Tangier Island, Virginia, USA, but some members of the town council objected to the drinking, cursing and sex in the movie and demanded script revisions in exchange for shooting permission. Warner Brothers then tried Martha's Vineyard near Chilmark, Massachusetts, USA, but the Chilmark Conservation Commission turned down a request to build a temporary 3,000-square-foot house on stilts in the dunes near Chilmark Pond.

The painting in Catherine's studio that Dodge carried outside during Garrett's encounter with Catherine's brother is "Girl With Lantern" by the American impressionist painter Helen Maria Turner. The painting, which was produced in 1904, is housed in the Greenville Museum of Art in Greenville, South Carolina, USA.

When Garret arrives at Theresa's apartment, the show playing on the TV that she turns off is Perfect Strangers (1986) The two main characters in that show worked at a Chicago newspaper, just as Theresa does.

Continuity

In his final letter to Catherine, Garret writes that he regrets watching Theresa get into a plane and fly away, but when she left him she drove away in a rental car (the airport scene was deleted).

Theresa rents different cars each time she goes to North Carolina, but they all have the same license plate (RZ-1553).

When Garret is typing the last letter to Catherine to tell her about Theresa, the first word he types is "It". When the letter is read in voiceover, it starts out with the word "My".

As Theresa opens her car door preparing to head back to Chicago, she turns and kisses Garrett goodbye. The car door closes and opens again between shots.

When Theresa and Garrett are at Garret's house for the steak dinner, he offers to pour her a glass of wine, which she accepts, but then begins to walk around his house empty handed. All of a sudden, while exploring, a glass of wine appears in her hand.



Factual errors

When Garret admires the hotel room near the start of the film, Theresa says it's Victorian, built in 1911. The Victorian era ended in 1901.



Revealing mistakes

Garret Blake's new boat is named Catherine, but the navel flags on the right side only say "atherine" without the C.

Toward the end of the film, during a storm, presumably taking place somewhere far out in the ocean, Garret Blake is in the water trying to rescue somebody. At one point, it looks as if he is just standing on the bottom of a pool, with water up to his chest.

When Johnny, Cathrine's brother, decides to help Garret build the boat, he takes a seemingly small square of wood and attaches it to the boat where obviously it does not belong there.

When Dodge, receives the boat after the death of Garret, one can clearly see that the mast spar has obvious wear signs, although it is a new boat and recently painted.



Errors in geography

The cars that Theresa rents have both front and back license plates. North Carolina doesn't use front plates.

Not sure if this is a mistake in the movie or a viewer missing something but if Catherine throws the bottle into the ocean while living in North Carolina how come Theresa finds it later while she's living in Chicago? The two places don't share the ocean.