Lake Silencio

Lake Silencio was located in Utah. On 22nd April, 2011, the Eleventh Doctor brought his companions to the lake for a picnic. At one point during the picnic, Amy Pond saw a member of the Silents off in the distance, but promptly forgot about it when she looked away. During the picnic, someone in an Apollo spacesuit emerged from the lake and shot the Doctor three times, apparently killing him. Amy Pond, Rory Williams, and River Song placed his body into a nearby boat, set it aflame with gasoline provided by an elderly Canton Delaware, and pushed it into the lake's water. (DW: The Impossible Astronaut)

The Teselecta's database contained a record of the Doctor's death at this lake, and revealed that Melody Pond was the woman who killed him. (DW: Let's Kill Hitler)

Dorium Maldovar claimed that the Silence chose this point in space because it was a "still point in time", and as such it was easier to create a fixed point in time. (DW : The Wedding of River Song)

When abducted by the Silence and Kovarian, River Song was placed in an Apollo spacesuit and submerged in the lake, to await the Doctor. (DW: Closing Time) Her subsequent refusal to kill the Doctor at the lake (a fixed point in time) caused time itself to collapse, with all of history happening at once. The Doctor averted this timeline by persuading River that his death was necessary and revealed to her that it was not him that she shot at the lake but the Teselecta, which had taken the Doctor's form. The Doctor was present at his 'death' but was safe inside the Teselecta and "barely got singed" by the funeral pyre. (DW: The Wedding of River Song)

Behind the Scenes

 * "Silencio" is both the Spanish and Italian word for silence.