The exclave was located at the tripoint between the current states of Idaho, Wyoming, and Montana.
Its borders ran along the Continental Divide, parallel 44°30' North, and the 34th meridian west from Washington.
Officially, the land was still a remote part of the Dakota Territory; however, it had been forgotten by the government, wiped from any potential public view that it could have had for around five whole years due to faulty maps and surveys.
Lost Dakota is extremely distant from settlement to this day and is completely undeveloped.
It is without a street, road, or even a footpath as of 2010, and lacks any signs or maps to locate the uninhabited area.