United Ireland achieved... 440 million years ago
Even if you already thought Ireland had a complicated history, you probably don't know the half of it.
The island we know as Ireland has been up to things most of us haven't a clue about.
For a start, the island is actually two separate land masses fused together.
The two parts joined up approximately 440m years ago, but that is neither the beginning nor the end of the story.
In a book launched on Wednesday, Belfast-born geologist Paul Lyle recounts the geological history of Northern Ireland and its neighbouring counties across the border.
Between Rocks and Hard Places brings together information from scientific, historical, archaeological and mythical sources.
Mr Lyle said Northern Ireland has a richer natural heritage than most people realise.
"This book aims to reveal how we can read the rocks and decode the secrets of our distant past and the tremendous events that have moulded the natural and cultural landscapes we now know.
The author shines a spotlight on a wealth of information known to scientists, but which may surprise the man or woman in the street.
For example, who knew that County Down was once a desert as hot as California's Death Valley?
Or that the two halves of Ireland arrived at their current location after drifting across half the planet from where Indonesia lies today?
A geological seam running from Shannon Town in County Clare across the island to Drogheda marks the boundary betwen the two halves, the book says.
Known as the iapetus suture zone, there is a noticable difference between the rocks on the northern side of the seam and those to the south.
The rocks on the northern island show it formed in the same part of the earth as Scotland.
The southern half is believed to share its geological origin with England and Wales
Over millions of years Ireland has undergone many transformations.
It sank under the ocean, became a tropical paradise and even hosted coral reefs which grew where there are now hills and fields.
More recently, volcanoes blasted the landscape, creating the Mourne mountains and the Giant's Causeway.
The land was then crushed under millions of tonnes of ice, a process which left behind areas of natural beauty such as Glendalough in County Wicklow and shaped the low hump-backed hills called drumlins which characterise the Northern Irish landscape.
Mr Lyle said that people in Northern Ireland have a unique record of the past at their fingertips.
"To the envy of many around the globe, it is possible for anyone here to easily see and examine rocks across almost the entire range of geological time," he said.
"We have been fortunate to be bequeathed with stunning natural wonders, such as the Giant's Causeway and the Marble Arch Caves, as well as a host of outstanding panoramas and views in a land rich in folklore myth and legend. This book is a celebration of the rich diversity of local geology and the stunning landscapes, culture and industry it has inspired."
Launching the book, in Belfast on Wednesday, the permanent secretary of the Department of Enterprise Trade and Investment, David Sterling said: "Our natural landscape in Northern Ireland is amazingly varied and this represents one of our unique selling points."
"Geology and landscape represent the natural foundation for much of our tourist industry from the Mournes to the Sperrins, from Slemish to the Fermanagh Lakelands. Northern Ireland is one of the best locations to study geology and landscapes."
Garth Earls, director of the Geological Survey of Northern Ireland, who contributed to the book said that the geology of the north of Ireland boasts as great a range of rock types as the whole of the European continent.
"It has been incredibly influential - inspiring rich folklore, contributing to key historical events and it continues to shape the very way we live our lives today."
Between Rocks and Hard Places is published by the Geological Survey of Northern Ireland and distributed by TSO.