Ever wondered where Halloween was born? Let us take you back 2,000 years to Ireland's eerie ‘Hell Cave’

As Irish folklore tells, a black horse with glowing eyes sprints through the Emerald Isle's raw countryside in the murky night, carrying a terrified countryman who can’t escape this ghastly ride. They gallop past eerie sites, which have now become tourist attractions – mystical fairy forts, prehistoric passage tombs, abandoned Royal capitals, and the ‘hell cave’ where Halloween was born.

While Halloween was popularised by the US in the 1900s, the holiday originated 2,000 years ago with Ireland’s pagan festival, Samhain. Now, Ireland is making moves to reclaim the celebrations, branding itself as the world capital of Halloween. An island-wide tourism campaign involving dozens of events, including fire processions, carnival parades, and Europe’s biggest Halloween festival has launched this month, in a bid to bring the holiday back to its original setting. Each event is designed around helping tell the creepy history of Samhain, during which supernatural beings ran riot across Ireland.

Inhabited for up 10,000 years, Ireland’s green fields, serene forests and raw coastline echo with riveting folklore. The Irish people respect the Celtic mythology, telling stories of these beings, like the aforementioned Puca horse. Some such tales are mere campfire stories, describing lost cities and invisible islands. Others are grounded in reality, like that of Samhain. Every November 1, on Samhain, Irish pagans would mark the Celtic New Year by chanting alongside bonfires at sacred sites such as Oweynagat hell cave – a supposed portal to Ireland’s mythical underworld, Tír na nÓg.

This subterranean realm bulges with Sidhe fairies, including leprechauns and pucas, which are infamous for supposedly abducting humans after dark. Sidhes are trapped in Tír na nÓg, which is supposedly separated from the living world by an invisible border. Every now and then, this barrier briefly dissolves. Sidhes emerge from the underworld to either save the Irish people or plunge them into disasters, like the Great Irish Famine, according to mythology. Samhain is the main moment this spirit invasion occurred.

During the early versions of this festival, Sidhes would pour out of Oweynagat cave and swarm adjoining Rathcroghan, the capital of Ireland’s ancient kingdom of Connachta. Meanwhile, Samhain’s human attendees prayed for protection from fairies, in between feasting, dancing and trading at Rathcroghan.

Now known as Europe’s largest un-excavated royal complex, Rathcroghan allows visitors to wander fields dotted by its 240 archaeological sites, including stone forts and ceremonial mounds. Tourists keen to known how Samhain inspired Halloween can join guided tours of Rathcroghan and Oweynagat, or they may attend the nearby Rathcroghan Visitor Centre, which has a small but informative museum.

There they learn that, in the 1800s, Irish immigrants brought Samhain to the US, where it gradually became a kitschy, commercialised festival aimed at children. Which explains why Ireland last year decided to plant its flag on this festival by launching its annual ‘Home of Halloween’ programme, says Julie Wakley, head of Great Britain for Tourism Ireland.

"Halloween is one of the most widely celebrated festivals globally, yet many people are surprised to discover that its roots trace back to the island of Ireland,” Wakley explains. Home of Halloween involves dozens of events across the entire island of Ireland – festivals, performances, food experiences, walking tours – and is a collaboration between Tourism Ireland and Tourism Northern Ireland. Northern Ireland is home to plenty of spooky places itself – including the Dark Hedges, a lane of overhanging beech trees, often used as a filming location in series such as The Game of Thrones.

Puca Festival (October 29 to November 1) in County Meath’s Boyne Valley incorporates heritage tours, live music events, a mythical character parade and a stunning fire procession that mirrors prehistoric Samhain rituals. Northern Ireland’s Derry Halloween (October 28 to November 1) is Europe’s largest Halloween festival, with events focused on storytelling, music, dance, fire shows, and a replica of an ancient Samhain harvest market.

Meanwhile, smaller Halloween festivals will unfurl in the cities of Dublin, Limerick, Galway, Longford and Kilkenny. Each of Ireland’s Halloween festivals is slightly different in character. But all have one thing in common: they aim to remind the world that, eons before sinister-looking pumpkins were carved by US kids, this festival was being celebrated by chanting, costumed Irish Pagans illuminated by bonfires. Ireland is reclaiming Halloween.

Ireland’s spooky sites to visit for Halloween

Oweynagat cave, County Roscommon

Some 2,000 years ago, Irish pagans accessed this ‘hell cave’ through a purpose-built entrance. Now, there’s only a narrow opening in a tranquil field, 140km west of Dublin. Tourists can peek into its dim interior, or read a nearby sign explaining its extraordinary history. But they’re not allowed to squeeze inside the cave, for safety reasons. No ticket is required.

Rathcroghan, County Roscommon

Grassy mounds rising from farmland contain remains of this Irish Royal capital, some 5,500 years old, which hosted ancient Samhain celebrations. During those rituals, shapeshifting beasts escaped from Ireland’s underworld to haunt Rathcroghan’s 6.5sqkm of forts, earthworks and standing stones. Visitors can access Rathcroghan at any time, for free. But it’s worth booking a 2.5 hour guided tour via nearby Rathcroghan Visitor Centre, for €21.20.

Rathcroghan Visitor Centre, County Roscommon

Located in tiny Tulsk town, 4km east of Rathcroghan, it has a café, gift shop, and petite museum. That latter facility, which costs €6 to enter, explains Rathcroghan’s ties to Samhain and Ireland’s eerie underworld, and displays ancient artefacts from this site. It is open year-round, Monday to Saturday, from 9.15am to 5pm.

Passage Tombs, County Sligo

Sligo’s mountainous countryside contains more than 100 eerie "passage tombs" up to 5,000 years old, including at scenic Carrowkeel and Carrowmore. It remains unclear who’s buried inside the majority of these stone tombs, the most spectacular of which is Keshcorran, overlooking majestic countryside. Local lore suggests Keshcorran’s tunnels are connected, underground, to Oweynagat "hell cave”. Entry is free, at all times, and it’s a moderate 15-minute uphill walk from the carpark.

National Leprechaun Museum of Ireland, County Dublin

Rather than providing a cartoonish explanation of leprechauns, this museum in downtown Dublin unravels the Irish folklore of Sidhe fairies. Visitors must join guided tours, which mix eyecatching video displays depicting Irish artefacts and ancient maps, with storytelling about Ireland’s supernatural beings. These 45-minute tours depart every 30 minutes, and cost €18 per adult.

Cnoc Meadha Fairy Fortress, County Galway

A dense, serene forest provides fine protection for Cnoc Meadha, the underground fortress supposedly home to Ireland's Sidhe fairies, who were key characters in Samhain lore. Visitors can take a scenic, 10-minute uphill walk from the carpark to reach this 1,000-year-old site, the legendary headquarters of the King of the Sidhes, Finvarra.

Tlachtga, County Meath

During ancient Samhain celebrations, bonfires glowed so intensely atop this 3,000-year-old ceremonial site that it was named Tlachtga, after a Celtic goddess of the sun. Now commonly called the Hill of Ward, it sits on private farmland in County Meath. But tourists can access it by joining one of the daily 90-minute Hill of Ward guided tours between October 29 and November 1, for €27.50 per adult.

Hill of Tara, County Meath

Blood stained the Hill of Ward during prehistoric Samhain rituals, which saw animals sacrificed to Pagan demons. This prehistoric Royal burial site, in emerald fields 18km east of Tlachtga, is now a heritage attraction, with free access to visitors seven days a week.