Flooded Alamo?
 
This was a photo from the Alamo in Texas. The Alamo was not flooded at the time I took the photo. I found out that the Alamo has been flooded for real before I started to ask people about what they thought about the Alamo being flooded while showing people this image. It was made even more believable solely because of it happening for real. I made this in Gimp while following a tutorial. The original post is on Flickr.