Speculation over the existence of a "southern land" was confirmed in the early 1820s when British and American commercial operators and British and Russian national expeditions began exploring the Antarctic Peninsula region and other areas south of the Antarctic Circle. In 1840, it was finally established that Antarctica was indeed a continent and not merely a group of islands or an area of ocean. Several exploration "firsts" were achieved in the early 20th century, but the area saw little human activity. Following World War II, however, the continent experienced an upsurge in scientific research. A number of countries have set up a range of year-round and seasonal stations, camps, and refuges to support scientific research in Antarctica. Seven have made territorial claims, with two maintaining the basis for a claim, but most countries do not recognize these claims. In order to form a legal framework for countries' activities on the continent, an Antarctic Treaty was negotiated that neither denies nor recognizes existing territorial claims; it was signed in 1959 and entered into force in 1961.  Also relevant to Antarctic governance are the Environmental Protocol to the Antarctic Treaty and the Convention on the Conservation of Antarctic Marine Living Resources.