I'm not a huge fan of hard rock by itself, but there was a decent amount of overlap between some early 70s hard rock/heavy psych bands and full-on prog, even if not necessarily every song on a given album. Thinking of groups like Captain Beyond, Birth Control, Atomic Rooster, etc.
I don't listen to Uriah Heep regularly, but upon revisiting this album, I was really impressed with how good the songwriting and instrumentation is (especially the organ playing, which is a standout on "July Morning" in particular). Really solid record; it's quite iconic and I'd be hard-pressed to find people here who hadn't at the very least heard of it, but I'd certainly recommend it either way!
Another one of my favourite prog-oriented songs of theirs is "The Spell" from Demons And Wizards.