From Howth station turn right on to Harbour Road. Continue west to Howth Road, with the station on your right. Cross the road and follow signs for the National Transport Museum (at the entrance drive to the Deer Park Hotel, Golf & Spa) and into the grounds of Howth Castle (also known as Howth Demesne). Follow the path towards the castle. Just before the castle building the footpath takes a right-angle turn. Follow the path until you reach a right turn for the National Transport Museum, clearly signposted. In 1949 a small group of transport enthusiasts made an unsuccessful bid to rescue three of Dublin’s last remaining tramcars from the breaker’s yard. They failed, but the National Transport Museum grew from that attempt. Its impressive collection includes a horse-drawn Merriweather fire appliance from 1883. In 1948 it was placed in storage in a disused distillery and forgotten about until 1996, when it was rediscovered and given to the museum. 

Turn about and retrace your steps with Howth Castle on your right. The castle grounds are most attractive in May and June, when the colourful azaleas are in full bloom. Although partly in ruins, the ancestral home of the St Lawrence family, Earls and Barons of Howth, is still lived in by descendants of the 1st Baron. The first castle was built here in the 14th century, but in the late 19th century Sir Edward Lutyens was commissioned to build a virtually new stately home on the site. In 1576, the famous female pirate Grace O’Malley made an impromptu visit to the 8th Baron, only to be informed that he was at dinner and she couldn’t come in. Peeved, she kidnapped the baron’s grandson (later the 10th Baron) and held him hostage until the baron pledged that the castle’s gates would forever be kept open to unexpected guests and an empty place would be set at each meal. The castle is open by appointment only. Since 2008 a cookery school, The Kitchen in The Castle, has operated from the castle’s wonderfully proportioned Georgian kitchens.

Retrace your steps to Howth station and follow the harbour promenade to the corner of Harbour Road and Abbey Street, with Howth Harbour on your left. The pretty harbour was formerly home to a large fleet of fishing smacks, but marine pollution, the massive over-fishing of the Irish Sea by Spanish and French trawlers, along with limits imposed by the European Union on how much can be caught, have virtually destroyed the local fishing industry and only a few crab and lobster boats share Howth Harbour with the numerous yachts and motor cruisers.

Cross Abbey Street and turn right down it. On your left (opposite the Abbey Tavern), you will see a squat, circular tower. Turn left to enter it. This is one of a chain of Martello towers built around 1804 along the coasts of Ireland, England and the Channel Islands to deter a French invasion of Britain and Ireland. Their name comes from a small medieval fortress on Cape Mortella on the French island of Corsica (ironically, the birthplace of Napoleon Bonaparte, the very man whose invasion plans they were intended to thwart). Somehow, Mortella was mis-transcribed as Martello and the name stuck. In 1805, soon after the towers were completed, the combined French and Spanish fleets were destroyed at the Battle of Trafalgar, the threat of a French invasion vanished, and the towers became redundant. In the 1840s this one was used as a telegraph cable station. On 25 November 1903 the American inventor Lee de Forest sent the first wireless radio messages from here to Holyhead in Wales, an achievement that was later overshadowed by the more famous Guglielmo Marconi, who also broadcast radio messages from this spot; Marconi seems to have been both a more adept self-publicist and more commercially minded than poor de Forest. Appropriately, the tower is now home to Ye Olde Hurdy Gurdy Museum of Vintage Radio, which houses hundreds of early radios, wind-up gramophones, Morse code transmitters and lots of other arcane pieces of broadcasting and communications equipment. In the era of the mobile phone, Bluetooth and the iPad, they look incredibly clunky – a reminder of how breathtakingly quickly technology has progressed in little more than a century. 

Retrace your steps, cross Abbey Street and turn left, passing the post office on your right, to the junction of Church Street, which forms a V. Between the two streets are the ruins and churchyard of St Mary’s Abbey, which was founded in 1042 by Sidric, or Sigtrygg, the Viking King of Dublin. Little or nothing remains of the original 11th-century building, and the roofless walls of the abbey date mostly from the 15th and 16th centuries. Like other monasteries and abbeys in Ireland and England, it fell into ruin and disuse after Henry VIII’s dissolution of the monasteries in the second half of the 16th century. The abbey ruins are not open to the public, but in the churchyard you can see the tomb of Christopher St Lawrence, 8th Baron Howth (whose grandson was kidnapped by the pirate Grace O’Malley) and his wife Elizabeth.

Turn right up Church Street to return to Harbour Road and walk back to Howth DART station for trains to Dublin. If you are feeling energetic, follow the Dublin Coast Trail, which starts at Balscadden Road opposite the Martello tower, along the cliffs back to the city (about four hours’ walking).