A pergola is an outdoor structure with a roof made of beams or slats that let sunlight filter through. Picture four posts holding up a grid of wooden crossbeams: you can see the sky through the gaps, but the structure creates patterns of shade below. People often build pergolas over patios or garden paths, sometimes training vines like grapes or wisteria to grow up the posts and across the top.

Unlike a gazebo, which has a solid roof that blocks rain, a pergola's open design means you'll still get wet in a downpour. But that's part of its charm: it creates a pleasant outdoor room that feels both sheltered and open to the air. The dappled shade makes hot summer afternoons more comfortable, and the beams overhead define the space without boxing it in.

The word comes from Italian, where it originally meant an arbor or covered walkway in a garden. Today, pergolas range from simple four-post structures in backyards to elaborate designs at parks and botanical gardens. Some modern pergolas include retractable fabric panels that slide across the beams, giving people control over how much sun gets through.