How many islands are in Indonesia? You might think that the answer “a lot” is a bit glib, but it turns out that the Republic of Indonesia itself doesn’t really know, either. The nation of many islands consists of so many small land masses that they have never been officially counted. Until now: As the BBC reports, Indonesia is embarking on an ambitious island census.

The census is a bid to mark Indonesian territory by registering the islands with the United Nations, the BBC reports. As the Financial Times’ Ben Bland explains, Indonesia fought hard for the legal concept of an “archipelagic state”—a country that controls not just the waters inside it, but around it. The concept led to a long definition in the UN Convention on the Law of the Sea, an international treaty that establishes how UN member nations deal with oceans.

That treaty contains another key definition, the BBC notes: one that describes an island. According to the treaty, an island is a natural land mass that is surrounded by water and that is not obscured by water during a high tide. Indonesia certainly doesn’t lack for those—but it can’t seem to keep its numbers straight. It’s submitted varying estimates of its number of islands over the years, perhaps because the definition of “island” doesn’t depend on whether it’s inhabited, above a certain size, or even named.

But the estimates are just that: estimates. With satellite technology, Indonesia upped its estimate from 17,508 in 1996 to over 18,000 in 2003. As the Indonesian news agency reported earlier this year, the hope is to bring the official UN count up to at least 14,572 named islands. But even that won’t take all of the country’s many unnamed islands into consideration.

Still, not all islands Indonesia claims are willing to stay there. In 2002, the International Court of Justice forced Indonesia to cede Ligitan and Sipadan, two tiny islands, to Malaysia, and after a 24-year occupation East Timor became an independent nation from Indonesia (also in 2002).

The total number of islands in Indonesia has big geopolitical implications. Voice of America’s Pete Cobus notes that the area is one of the world’s most important waterways, home to a third of the world’s maritime traffic and up to $5 trillion in trade. Indonesian vessels recently clashed with Vietnamese ones in the area, and questions of sovereignty continue to roil the waterway.

With maritime tensions in Asia on the rise, fueled by controversy over island ownership in the South China Sea, not to mention climate concerns—thousands of Indonesia’s islands are threatened by rising seas—and fears of private companies taking over small islands, there's no doubt that numerical drama will play out at the UN Conference on the Standardization of Geographic Names this summer when the conference decides which names go on official maps.

But first, Indonesia must finish its own big task—counting all of those islands.