There were many things that attracted me to Basel for my doctoral studies, not least of which was the fact that it was in this city that Calvin, at the ripe old age of 27, published his Institutes of the Christian Religion in 1536, a work that provided the seeds for the branch of Christianity that bears his name. If you want your faith to be stretched, read this book. If you want to improve your German, then listen to this outstanding lecture by Karl Barth.
I have never regretted my years in Basel. They formed the foundation of what turned out to be a most pleasant career as a teacher of the New Testament. I cannot thank God enough for that.