Flores's geosites: crater lakes, Rocha dos Bordões, the valleys and the westernmost rock in Europe

Flores is a high plateau of explosion craters, cut by deep stream valleys and ringed by cliffs. The Azores Geopark picks out 14 places on the island as geosites, numbered FLO 1 to FLO 14, more than on any other island in the western group. Most can be seen from a road, a viewpoint or a boat, and between them they explain the shape of the island. This guide takes them in the order you would meet them on a loop from Santa Cruz: what you are looking at, and where to stand to see it.

Four words do most of the work. A maar is a crater blown out when rising magma hit water and exploded; most of the lakes on Flores sit in one. A volcanic chimney (chaminé) is the hardened plug of rock left in a vent after the softer cone around it has worn away. A dyke (filão) is a wall of rock that formed when magma filled a crack. A fajã is a flat strip of land at the foot of a cliff, made by lava running into the sea or by the cliff falling down.

The Geopark's own list, with its numbers:

• FLO 1: the Negra, Comprida, Seca and Branca craters
• FLO 2: the Rasa and Funda craters above Lajes
• FLO 3: Fajã Grande and Fajãzinha
• FLO 4: Pico da Sé
• FLO 5: Ponta da Rocha Alta and Fajã de Lopo Vaz
• FLO 6: Rocha dos Bordões
• FLO 7: the north-east coast
• FLO 8: the Filão dos Frades
• FLO 9: the coast at Santa Cruz
• FLO 10: Ponta do Albarnaz to Ponta Delgada
• FLO 11: the Ribeira da Cruz valley and Ponta da Caveira
• FLO 12: the Badanela and Além da Fazenda valleys
• FLO 13: the Lajes valley and lava fajã
• FLO 14: the Ilhéu de Monchique

The English pages on the Geopark website cover the first six; the descriptions of FLO 7 to 14 are only on the Portuguese pages. Looking at them costs nothing. Several sit inside the Flores Nature Park, whose 2026 management plan sets rules on where you may walk; our guide to the Nature Park rules has them.

Start in town. The shore at Santa Cruz is a run of rocky points with small bays and coves between them, which is where the natural pools are. The points are trachyte lava, mostly buried under dark basalt cinder thrown out by Pico da Cruz, the hill above the town, which was once quarried. In the Boqueirão environmental interpretation centre, in the tanks of the old whale factory, the rock comes straight through the walls into the building. The centre is about the island's sea, birds, whales and hydrothermal vents. Our Santa Cruz guide has the walk round town.

South of Santa Cruz, the Ribeira da Cruz runs through a wide valley with several basalt chimneys standing up out of it. The Geopark calls them one of the island's geological emblems. A waterfall splits the upper and middle parts of the stream, and above it is the Poio Moreno spring, mineral water that comes out at 24.8 °C with a pH of 6.5.

Where to look: the Miradouro dos Arcos, on the road from Santa Cruz up to the lakes, looks over the whole valley.

Ponta da Caveira is the steep headland just north of the mouth of the stream. At sea level its basalt cliffs hold the Gruta dos Enxaréus, a sea cave about 50 metres long and 25 metres high that you can only reach by boat. Cave tours from Santa Cruz go in when the sea allows; Flores Fishing listed a three-hour tour at €60 a person in 2026, minimum two. Our boat trips guide compares the operators.

These two belong together. Pico da Sé is a trachyte dome, about a kilometre across at the base: lava so thick that it piled up over its vent instead of flowing away, so its sides are steep. Two streams, the Ribeira da Badanela and the Ribeira d'Além da Fazenda, have cut deep V-shaped valleys around it. In doing so they exposed the chimneys and dykes inside the older rock, and these now stand out from the green slopes as walls and ridges.

The two streams meet at a small dam and run on as one. In the last stretch, around the Pisão hydroelectric plant, the rock in the bed and the banks has cooled into columns.

Where to look: the Miradouro da Casinha, on the road from Santa Cruz to Fajã Grande, faces Pico da Sé and the valleys. The Geopark also points out that canyoning is a way into these valleys; our canyoning guide lists who guides it.

From the mouth of the Além da Fazenda stream north to the bay where the Ribeira Funda comes out, the coast is high cliff with waterfalls, pebble beaches, sea caves and islets. The basalt flows have cracked into columns, best seen in the sea cliffs, and in places into rounded blocks. The Geopark names the islets (Furado, Álvaro Rodrigues, Garajau and Alagoa), the Furna do Galo sea cave, which you can reach by boat, the Baía da Alagoa with its picnic park, and the columns at the mouth of the Além da Fazenda stream.

Where to look: the viewpoints on the regional road north of Santa Cruz, or from a boat. The Miradouro dos Caimbros, above the Alagoa bay, gives the best view of the beach and the islets. Our guide to the north of Flores covers the drive.

The north coast is a line of tall, steep cliffs made of layer on layer of lava and ash, cut through by chimneys and dykes. The coast is so straight that the Geopark thinks faults control it. At the little harbour of Ponta Delgada the basalt has weathered into balls. The fishermen's paths down to the sea, such as the Portal do Vento, are the way to see the cliffs from close up.

The Albarnaz lighthouse stands on this geosite. It was lit on 28 January 1925 and looks over the channel to Corvo.

The trail PR01FLO starts here, runs past the lighthouse and along the cliffs to Fajã Grande. When we checked the official alerts page on 9 October 2026 it was listed as temporarily closed, so do not plan on it without checking trails.visitazores.com first.

Up on the central plateau, the Caldeira Negra, Caldeira Comprida, Caldeira Seca and Caldeira Branca are maars. All have a lake except Seca, the dry one. The Caldeira Branca has a low ring of tuff around it. The lake in the Caldeira Negra is 108 metres deep, the deepest in the Azores according to the Geopark, and the reason for its other name, Caldeira Funda (the deep crater).

Where to look: the Miradouro das Lagoas, on the forest road off the ER 2-2, shows Negra and Comprida side by side. For the wider view of the plateau and its shallow, flat-bottomed streams, the Geopark suggests the top of Morro Alto; our Morro Alto guide has the road up. Cloud often sits on the plateau; wait a few minutes before you give up.

The west coast drops off the plateau down a fossil sea cliff about 300 metres high. At its foot are two lava fajãs, partly buried under rubble from the cliff and gravel brought down by streams such as the Ribeira Grande. Water falls off the cliff in many places and collects in pools at the bottom; the best known are the Poço do Bacalhau and the Poço da Alagoinha, also called the Lagoa das Patas.

Where to look: the Miradouro do Portal, at the top of the road down, shows both fajãs and the villages of Fajãzinha, Fajã Grande, Ponta da Fajã and Aldeia da Cuada. Our west coast guide and waterfalls and lakes guide cover the walks to the pools.

Out to sea off the west coast, about 1,500 metres from the shore, is a single rock about 30 metres high with an area of roughly 3,000 square metres. It is the westernmost point of Europe. It is what is left of a volcanic cone that the sea has worn away, standing on an underwater shelf of lava 40 to 50 metres down. Because it was the first land a ship met coming from the west, sailors used it to check their course and their instruments.

Where to look: from the west coast around Fajã Grande and Ponta da Fajã, on a clear day.

Between Mosteiro and Lajedo, a hillside of upright stone columns rises above the road. Bordões means staffs or walking sticks. The columns formed as a lava flow about 570,000 years old cooled and cracked. They are about 20 metres tall and a few tens of centimetres across, and the trails register counts more than 200 of them.

Where to look: the Miradouro da Rocha dos Bordões, on the ER 1-2. The 2026 Nature Park management plan prohibits public access to the rock itself, so look from the viewpoint and the road. The columns show best in side light, in the morning or late afternoon.

On the southern part of the plateau, two more craters from the same kind of water-and-magma explosions sit next to each other, with lakes at very different heights: the Caldeira Funda lake at 360 metres and the Caldeira Rasa lake at 530. The difference comes from their shape. Funda is a maar, a crater sunk into the ground, while Rasa sits inside a ring of tuff built up around its vent. Several streams drain into Funda.

Where to look: the Miradouro da Caldeira Rasa e Caldeira Funda, on the paved forest road Caminho Florestal dos Rochões, shows both from one spot.

Below those two craters, the valley of Lajes, also called Boca da Baleia, runs about 3 kilometres down to the town. It is wide and straight, and the Geopark thinks it may have formed as a block of ground dropped between two faults. The Ribeira das Lajes runs along one side and the Ribeira Seca along the other. Lava from the Boca da Baleia area flowed down it to the sea and built the rocky point that Lajes das Flores stands on.

Where to look: at the Praia da Calheta, by the town, you can see the old sea cliff that the lava flowed over and around. It now stands back from the shore as a fossil cliff about 300 metres long, as far as the Ribeira das Lajes. Our Lajes das Flores guide covers the town.

West of Lajes the south coast cliffs have collapsed into two fajãs of rubble. Fajã de Lopo Vaz faces south, has a spring and a beach of dark sand and pebbles, and you can only reach it on foot. Ponta da Rocha Alta, just west of it, is new: it formed in 1985. In the cliff above them, basalt at the bottom grades into trachybasalt towards the top, with a few dykes cutting through.

Where to look: the Miradouro da Fajã de Lopo Vaz, about 3 kilometres west of the centre of Lajes by narrow lanes, has a view over both. The trail PRC04FLO goes down from there: 3.4 kilometres there and back, about two hours, graded medium, with stone steps and a real risk of falling rock under the cliff.

The Filão dos Frades is a dyke of trachyte that stands up from the surrounding fields like a wall, because the older rock around it was softer and wore away. It runs north-north-west to south-south-east and ends at the cliff above Fajã de Lopo Vaz. The Geopark names no viewpoint for it, and we could not confirm a stopping place, so treat it as something to look for on the way to the Lopo Vaz viewpoint rather than a stop of its own.

Most of these are short stops from a car. A simple split is by side of the island: the east from Santa Cruz (FLO 9, 11, 4, 12, 7), with Ponta Delgada and Albarnaz (FLO 10) at the end of the north coast road; then the lakes, the west coast, Rocha dos Bordões and the south (FLO 1, 3, 14, 6, 2, 13, 5) on another day. The plateau is often in cloud while the coast is clear, so check the morning sky and swap the order if you need to. Our Flores weather guide explains how to pick a coast by the wind.

How many geosites does Flores have? Fourteen, numbered FLO 1 to FLO 14 by the Azores Geopark.

Do the geosites cost anything to visit? No. They are viewpoints, roadsides and coastline. A boat trip to the sea caves costs extra; one operator listed €60 a person in 2026.

Can I walk up to Rocha dos Bordões? No. The 2026 Nature Park plan prohibits public access to the rock. Look from the Miradouro da Rocha dos Bordões on the ER 1-2.

Which geosites need a boat? The Gruta dos Enxaréus at Ponta da Caveira and the Furna do Galo on the north-east coast are only reachable by sea. The Ilhéu de Monchique is a rock in the sea that you look at from the west coast.

• Azores Geopark: geosites of Flores
• Azores Trails: alerts
• Visit Azores: Ilhéu de Monchique
• Flores Fishing: caves and waterfalls tour