Reminder that there is one plot of land left on Earth (besides Antarctica) that is not claimed by any nation. It's just located between Egypt and Sudan. So if you are looking to start your own country, city-state, autonomous zone, or whatever without secession, now is your chance.
https://en.wikipedia.org/wiki/Bir_Tawil
Technically, there is also a no man's land between Croatia and Serbia but a minarchist libertarian has already claimed it and is really committed to it.