It’s been a pretty spectacular morning. You rode a ferry to a remote island. You docked at the island’s only town, which is filled with white houses with terra-cotta roofs. You passed green pastures, black stone walls, and steep cliffs as you headed inland. Then you followed a trail into a volcanic crater. Yes, a crater.

That crater is on the island of Corvo. The smallest and the northernmost of the Azores lies nearly 1,000 miles off the coast of Portugal. The island’s first permanent settlement was established in 1580. Less than 500 people live on the remote, seven-square-mile island today. Most people live in Vila do Corvo, a rare flat area on the southern coast. Farms and fruit orchards spread beyond the village. A biosphere reserve covers the rest of the island, including the Caldeirão.

The Caldeirão (caldera), on Corvo’s northern coast, is the result of a collapsed volcano. The elliptical-shaped crater is 2.3-kilometers wide and more than 300-meters deep at its largest points. It’s filled with spatter cones, cinder, peat bogs, and, most amazingly, a lake, Lagoa do Caldeirão. Nine islets—one for each of the Azores, according to the islanders—sit within the shallow lake.

The lake and its islets were barely visible when you started hiking down into the crater. From Ponta do Marco, the observation lookout, you could see the path in front of you and a large stone ahead, but everything else was pretty gray. Fog obscured everything. But you carefully followed the signs, crossed small streams, and passed wetlands. You listened for snipes and watched for nesting mallards. Then, as you reached the bottom, it finally started to clear.

You’re standing on the edge of the blue-green lake. It extends well beyond its usual boundaries, due to recent heavy rains. A little beach is on the left bank. Steep, green cliffs rise from the sides. They’re dotted with black lava. While those streams you passed on your way down now look like rushing rivers. You’re giddy with excitement and trying to take a picture that includes both you and this massive crater. It doesn’t matter what you do the rest of the day—and maybe the rest of the trip. This spectacular view is the highlight of your trip to the Azores.