Overview
The traffic-free part of National Cycle Route 99 is the Comber Greenway – seven miles (11 km) of old railway line running from Dee Street in East Belfast out to Comber. That stretch is flat, surfaced and safe enough for children, with proper crossings where it meets the main roads. The rest of Route 99 is a different proposition: quiet County Down roads that skirt the Ards Peninsula and the southern shores of Strangford Lough, then run down to Newcastle under the Mourne Mountains.
It’s worth being clear about that from the start. Despite the name, this is mostly an on-road touring route, not a segregated greenway. If you want a family spin, ride the Comber Greenway and turn back. If you want the full run to Newcastle, you need to be comfortable sharing quiet roads with cars.
The route is free, open year-round, and connects with National Cycle Routes 9 and 93 at the Queen Elizabeth II Bridge in Belfast.
Along the route
From Comber, the road works south around Strangford Lough, a designated Area of Outstanding Natural Beauty and one of the best birdwatching spots in the north. This shore is thick with places to stop: Scrabo Tower above Newtownards, the Wildfowl and Wetlands centre at Castle Espie, and the early monastic site at Nendrum.
At the tip of the peninsula, Portaferry faces Strangford across the fast, narrow mouth of the lough. Exploris, Northern Ireland’s aquarium, is here. The crossing itself is the highlight of the ride: the Portaferry–Strangford ferry runs year-round and carries bikes free of charge (foot passengers pay about £1 each way), and it saves a long detour around the head of the lough.
From Strangford the route heads inland to Downpatrick, a natural halfway point, with the Saint Patrick Centre and Inch Abbey nearby. Delamont Country Park sits on the shore north of the town. From Downpatrick the road runs south through quiet countryside to the dunes and long strand at Newcastle.
Cycling conditions
- Surface – tarmac throughout, with some minor surface wear on rural stretches. Standard road or hybrid bikes are fine; you don’t need anything off-road.
- Waymarking – the yellow-on-black National Cycle Network arrows are reliable, but carry a backup: load the route onto a GPS or phone before you set off.
- Traffic – generally light outside summer weekends, but stay alert at junctions and through town centres.
- Servicing – bike shops in the larger towns stock puncture kits and basic spares; rural stretches between villages have little.
Getting there and around
The route ties into Northern Ireland’s public transport, so you can ride one-way and take the train or bus back.
- Trains – bikes are carried on NI Railways services (including the Belfast–Bangor line), though space is limited at peak times.
- Buses – Ulsterbus and Goldliner services will take bikes on most routes; advance booking is advised in busy periods.
- Ferry – the Portaferry–Strangford crossing runs year-round; bikes travel free.
Tips for cyclists
- Plan for on-road riding. High-visibility clothing and reliable lights matter here, especially on the coast where fog can come in fast.
- Pack for weather. County Down’s exposed shoreline changes quickly – carry a waterproof even in summer.
- Dogs. Leashed dogs are welcome on the beaches at Newcastle; the nearby Murlough Nature Reserve allows dogs on leads year-round, with restrictions during the bird nesting season.
- Refreshments. Stock up in Newtownards, Downpatrick or Newcastle; the stretches in between are thin on cafés.
If you do only one thing on Route 99, make it the Portaferry–Strangford ferry: five minutes across the mouth of the lough, free with a bike, and the part of the day you’ll remember.