Cathar Castles and the Roussillon Coast

Walk the full circuit of the lices, the corridor between the two walls, and work out where the 112 workers' houses stood that filled it in the 19th century when the towers were being used as garages and sheds and the walls were being quarried for stone — the demolition of the whole Cité was already scheduled when Jean-Pierre Cros-Mayrevieille stopped it

Start at the Belvédère, which needs no climb and puts all four castles in one view, then take the made path along the crest and reach them in their north-to-south order — Cabaret, the Tour Régine, Surdespine, Quertinheux — about two and a half hours on the ground

Find the two separate doors into the same abbey — it was sold off in two lots at the Revolution and has never been put back together, so the medieval half belongs to the Aude department and the rest to a community of canons — then go into the public half for the private chapel abbot Auger de Gogenx had built in 1296, with its upper and lower chapels, and look at where the plain medieval masonry runs straight into the 18th-century classical work in flamed ochre sandstone

Walk down into the dry bed of the Cesse and go right through the Pont Grand, 228 m of natural tunnel, then carry on upstream to the 126 m Pont Petit

Stand in the five bays of the nave, under a broken-barrel vault twenty metres up that the monks built first, against all Cistercian practice, as soon as the house joined Cîteaux — then look at the windows and notice what should not be there: the rule allowed only grisaille glass, and every window you see came out of the Fayets' own glassworks in 1913, with the five in the north aisle telling the life of Saint Francis of Assisi

Walk the two kilometres east out of Tuchan and up the 96 m hill, and from the walls work out how much of the plain one man could keep an eye on: for all this stonework, the whole garrison in 1302 was the castellan, twelve sergeants, a porter, a single watchman and a chaplain

Walk up to the ruins on their spur and find the grand logis of the royal period, which was only dug out of the rubble in 2007 — then use the site's own panels to work out which walls belong to the lordship Montfort besieged and which to the royal garrison that came afterwards

Climb to Peyrepertuse and up the Escalier de Saint-Louis, the steep stair cut into the rock, to the Sant Jòrdi keep at the top of the ridge

Work round the three courtyards of the Palais des rois de Majorque naming what each wing did: the Palais Blanc to the west, probably the throne room; the Salle des Timbres to the north where the council met; the two stacked chapels to the east, Sainte-Madeleine below and Sainte-Croix above; and the Salle de Majorque to the south where the king held parliament and gave judgement. Look for the mudéjar decoration grafted onto the Gothic

Follow the Chemin du Fauvisme, the trail of reproductions of Matisse's and Derain's 1905 paintings set up where they painted them

Walk the circuit of Vauban's walls at Villefranche and find all three parts of the UNESCO ensemble from the ground: the enceinte itself, Fort Libéria on the slope above, and the entrance to the Cova Bastera caves cut into the rock at the foot of the wall

Put a hand on the forged iron cross at 2,785 m and work out what it took to get it there: the Notre-Dame-la-Real scout troop of Perpignan carried it up from their meeting rooms in the town in 1943, in the middle of the occupation — and look at what it is bolted into, an orthogneiss that began as granite 425 million years ago and was cooked into its present state when the Pyrenees' ancestors were built