Once we learned what Venus was really like, it became a sort of forbidden planet for science-fiction writers — but human colonies aren’t totally out of the question:
To my surprise there has even been some credible discussion of colonization — not of the hellish surface but the upper atmosphere, with aerostats AKA balloons. At 50 km above the surface the atmospheric pressure is equal to Earth’s, and temperatures are near the human comfort zone, 0–50° C. Human breathing mix is a lifting gas on Venus (with roughly half the lifting power per cubic meter of helium on Earth), so the entire gas envelope can contain breathing air. Venus gravity, about 0.9 g, is suitable for human health, while Mars’ third of a g is probably not enough.
Humans could even go outside, in principle with nothing more than a breathing mask, though protective clothing against those sulphuric acid droplets in the atmosphere would be a good idea. And don’t lean over that rail too far. It’s a looong fall, and nasty down below.
Reaching an aerostat base from orbit is (relatively) simple. Getting back up is challenging but not impossible, Venus orbit lift being a shade easier than Earth orbit lift.
If you really want to walk on the surface, consult the psychological or religious advisor of your choice. Returning to aerostat level is straightforward, a skyhook balloon, but that and your cooling system should be very reliable.
Every month it seems I end up back at this wikipedia article: Terraforming of Venus. And the more I read it, the more it makes sense. Day/night cycles, the size of the planet. Let’s do it.
From what I (just) read, terraforming Venus is far beyond our capabilities — but colonizing Venus is still conceivable, because floating cities could get around most of the problems: