Continuity mistake: On the ferry, Rachel wears the purple/pink camouflage hoodie OVER her orange knit sweater with the colorful stripe sleeves, as usual. Now this is where things become strange. In the first shot as the trio come ashore, she is only wearing her orange sweater, she is not wearing the purple/pink hoodie note the clear lack of fur hood. In the very next shot as they climb a bit more and then rest, Rachel is wearing the purple/pink hoodie note the hood, but now it's on UNDER her orange sweater. In the underwater shots she is also wearing it under the orange sweater. (This odd mistake has absolutely nothing to do with the very long wool cloak that Rachel wears in the next scene.)
Other mistake: When Ray pulls up to Mary Ann's home, the front exterior layout and dimensions of the house are evident, from its near center front door to the two car garage, in front of Ray's van. The side exterior wall contains two large garage doors, which are about 35-40 ft from the location of the front door, with no small basement windows at ground level; inside, beside the front door, the stairs that lead to the basement run parallel just under the stairs in the foyer. In the basement, the small windows on the far end of the furnace room they run into are only about 20 ft from the basement stairs. Not only are the small windows non-existent in the exterior shot, but it's entirely impossible for two small windows to be where they are, considering the exterior footage of the house.
Continuity mistake: When the ferry casts off in the wideshot, there are only six people hanging off the outer edge of the ramp as it's being raised. When Robbie and another gentleman help these people over, in the close-up one of them wears tan pants, a long blue coat and knit hat, but this person was not amongst the six in the previous shot.
Trivia: In an early scene in which Rachel is watching television, she's channel surfing. At one point, she hits briefly upon a shot of a car being demolished by a speeding locomotive. This is, in fact, a scene from "The Greatest Show on Earth," which Steven Spielberg has reported as the first movie he ever saw.
Trivia: When a group of aliens are exploring in the cellar, one of them spins the wheel of an overturned bicycle, and all are startled when the bicycle falls, making for a moment of comic relief. There's more to it, though. The H.G.Wells book mentions that the aliens probably had no concept of the wheel, as not a single rotating part was found inside the captured tripods. So an upside-down bicycle must have puzzled them a great deal.