A salubrious place is clean, pleasant, and feels good to be in — the sort of street or hillside you would rather live on than the noisy, dirty one next door. The word comes from Latin for healthy, but in English we use it about places and areas, not about pills or exercise. It is quite formal, even a little posh, and though actually it is often used with a raised eyebrow. Writers love the phrase a less than salubrious neighbourhood, which is a polite way of saying the area is rough, seedy, or a bit unsafe. So the tidy meaning is clean and wholesome; the way people really talk often includes a joke or a gentle insult.