Abstract: An inflatable marking device for marking a position comprising an inflatable balloon for receiving a lighter than air gas for inflating the balloon to cause the balloon to rise to mark a position. A line is secured at one end around the throat of the balloon and at the other end to a handle to maintain the balloon at the desired position. The handle is provided with a nipple for receiving the throat of the balloon, a spool around which the line is wound, and a shoulder to keep the line from overlapping onto the nipple when unwinding the line from the spool. One end of the handle is an opening for sealing around a gas cartridge when the cartridge is inserted therein, and a pin valve is positioned within the opening for engaging the cartridge to cause the gas to escape from the cartridge, through the nipple, and into the balloon.