IronDeer Gravel Challenge: 130km Mountain & Coast Loop

Who this tour is for

This is the hardest day in the Irondeer programme. 127 kilometres and 2,172 metres of climbing across the Serra de Aire e Candeeiros, down to the Óbidos Lagoon and back up the Silver Coast is a full endurance day by any standard. It is designed for riders who already do long days on the bike and are comfortable managing effort and nutrition across seven to nine hours in the saddle.

The route runs on gravel and tarmac throughout, with the mountain sections on compacted limestone tracks and forest gravel. The Irondeer Gravel are the bikes for this day - gravel geometry handles everything the route asks of the rider from the first forest track to the long coastal return. This tour is guided on every departure.

Out of Fanhais

Same start as every other loop, same pine forest east. The difference is visible by kilometre 20, when the limestone ridgeline ahead starts to look like a wall. Save the legs for what comes next.

Into the Serra de Aire

The climb begins in earnest after the Aljubarrota valley. The Serra de Aire e Candeeiros Natural Park stretches between Ourém in the north and Rio Maior in the south - the most important limestone deposit in Portugal, a karst massif of Jurassic rock approximately 160 million years old. The route passes close to the Alvados cave system on the ascent - a network of underground chambers and lakes beneath the limestone plateau, including the Catedral chamber with a 20-metre-high ceiling. Above ground the landscape shifts: pale rock, scrub oak, dry stone walls, no shade. The route crests at 598 metres on the open plateau with the Atlantic visible to the west. The same Serra de Aire that appears on the horizon during the Nazaré to Fátima pilgrimage route is the mountain you are riding through today.

The southern descent

From the summit the route descends south through the heart of the natural park for 25 kilometres, dropping from 598 metres toward the lower ground between the Serra and the coast. This is the most remote section of the day - limestone terrain, sparse villages, the park's interior. At the bottom the landscape flattens, the rock gives way to farmland, and the route turns west toward Caldas da Rainha.

Caldas da Rainha

The route passes through Caldas da Rainha - founded in 1484 when Queen Leonor, travelling through the area, stopped at a thermal spring and bathed in it on the advice of local peasants who claimed it had healing properties. She was cured, returned, and built a hospital and a town around the springs. The Thermal Hospital of Caldas da Rainha, founded in 1488, is the oldest still-operating thermal hospital in the world. The town is also known for its ceramic tradition, particularly the earthenware produced at the Bordalo Pinheiro factory - distinctive, irreverent, and exported worldwide. The route passes through without a long stop. There is a café if the group needs one.

Lagoa de Óbidos and Foz do Arelho

The route arrives at the Lagoa de Óbidos - one of the largest coastal lagoons in Portugal, a tidal system connected to the Atlantic through a narrow channel at Foz do Arelho. The lagoon is known for its oysters and its birdlife - the same stretch of water covered on the Óbidos Lagoon Birdwatching Tour, at a very different pace. Foz do Arelho is the furthest point south and west of the day. From here the route turns north and does not turn again until Nazaré.

North along the Silver Coast

The return runs up the Silver Coast, the stretch of Atlantic shoreline between Foz do Arelho and Nazaré. The wind on this coast typically blows from the north - which means the return ride into Nazaré is usually into the wind. At this point in the day the legs have covered 95 kilometres and climbed 1,800 metres. The last 30 kilometres are the test.

Into Nazaré

The route comes off the coastal road and enters Nazaré through the port - the working harbour at the south end of the beach, where the fishing boats come in and the catch has been landed on this same stretch of sand for centuries. From the port the track runs north along the main beach, Praia de Nazaré, with the Atlantic on the left and the town on the right. At the end of the beach the road climbs back up to the start. 127 kilometres, 2,172 metres. The legs know it.