99% Invisible is a great podcast about design, architecture, and related fields. I can’t recommend it enough: exquisitely produced, intriguing content, engaging host.
To give you an example of the range of stories they cover:
A phone booth in the middle of the Mojave Desert, half-built houses in Chile, Portland airport… carpet, IKEA hacks, underground tunnels in Cold-War era Berlin… I could go on, but you get the picture.
(and they’re also a part of Radiotopia, which is an independent podcasting network, if you need more good stuff to listen to).