Aalto won the design competition in 1929 and the sanatorium was completed in 1933, at a moment when the only reliable treatment for tuberculosis was rest, clean air and sunlight. Every decision follows from that. Ceilings were painted a soft greyish green so patients lying on their backs would not be staring into glare. Lamps sit outside the line of vision. Cupboards were fixed to the wall clear of the floor so cleaners could sweep beneath them. At the end of each ward wing there are sunning balconies where the weakest patients could be wheeled out in their beds, and the top floor opens onto a full sun deck for those strong enough to walk. Patients typically stayed for years, so Aalto designed for a community, not a queue: communal rooms, a chapel, staff housing, and walking routes laid out through the surrounding forest. He and Aino Aalto designed the furniture too. The Paimio Chair was built for patients who would sit in it for hours every day, its cantilevered birch bent to an angle Aalto argued was the one at which a tubercular chest breathes most easily; Artek still makes it.

A surgery wing was added in the 1950s, drawn by Aalto's own office. Then antibiotics arrived and tuberculosis effectively vanished as a mass killer, taking the patients with it. Through the 1960s the sanatorium was converted into an ordinary general hospital, which is a strange fate for a building designed around one specific disease. Turku University Hospital still owns it, but it has not been a hospital for years; since 2014 the main building and some staff houses have served as a rehabilitation centre for children and young people, run by a foundation the Mannerheim League for Child Welfare established in 2000. Visitors can now walk the corridors themselves - it is open daily except Mondays through the summer, and Tuesday to Saturday into the autumn. In July 2026 it was inscribed as one of thirteen sites making up Aalto Works, a World Heritage listing recognising the buildings of Alvar, Aino and Elissa Aalto under criterion ii, for what UNESCO described as a human-centred, site-specific and empathetic vision.

Paimio sits on the Paimionjoki, which is the largest of all the rivers draining into the Archipelago Sea, both by catchment - 1,088 square kilometres - and by flow. North of the centre the river runs for about seven kilometres through the Paimionjokilaakso, a 156-hectare Natura 2000 valley and one of the oldest cultivated landscapes in Finland. Grazing kept the slopes open for centuries. When it stopped in the 1950s the spruce began moving in, and restoration work started in the early 1990s to push it back out again. Downstream the river empties into Paimionlahti, a long narrow bay of reed beds and wet meadows, protected across 221 hectares and rated internationally significant as a resting place for migrating birds. Two towers on the eastern and northern shores let you watch it happen.

The parish is old - it marked its 650th anniversary in 1975. St Michael's Church, in Vista village, is a towerless single-nave hall of grey stone built between 1681 and 1689 and consecrated on Christmas Eve of that year by Johannes Gezelius the Younger; it seats around six hundred. Out at Hevonpää by the bay stands St James's Church, red brick on a grey stone base, built 1926-1928 to designs by Lars Sonck after fire took its predecessor. It seats two hundred, has a mosaic Head of Christ by Oskari Niemi from 1928 above the altar, and keeps a separate wooden belfry that Joonas Wrigstadius raised in 1734, its bells cast in 1744 and 1875. Beside it is the Rehbinder family burial chapel of 1824, designed by Carl Ludvig Engel. Then there is the railway station: a Bruno Granholm building opened in 1899 and extended in 1916, standing on a working main line where no passenger train has stopped since 1988. A local Pentecostal congregation uses it now. Regional services from Turku have been discussed since the 1990s and are still only discussed.