I was conducting a bit of a thought experiment where you would take a very tall column of water and put it in an environment where it should boil, like <100C at sea level. The water at the bottom of the column is under more pressure than the water in the middle, which is under more pressure than the water at the top. It may help if we assume the water in the column is at a uniform temperature, the same as the environment.
Say that in this environment, the water at the top and middle has a vapor pressure greater or equal to the pressure over the water at that point, so that bubbles of vapor can form. If the water in the bottom of the column was at such a high pressure that the vapor pressure of the bubble would not be enough to support the bubble over the pressure of the water, would the boiling appear on a boundary in the middle of the column, or off the side walls, and suddenly stop boiling when the water reaches a certain depth where the water pressure is too high?