I was at Cambridge, early 2000s, humanities subject, but with some science crossover. My subject was known for having a high workload for the humanities.
There was a full lecture programme, though after the first year I didn't attend very regularly (too busy with my extra-curriculars). I had about two essays and two supervisions a week, so yes, it was pretty intense. I did a huge amount of extra-curricular stuff too.
I found the eight weeks of intensity followed by taking it easy with a holiday job suited me well, but I did know people who struggled.
Bear in mind, you're not supposed to agonise over the essays, the idea of setting so many is that you learn to write them quickly, as you would in the exams. The term time essays do not count towards anything, they're essentially all practice for finals. I found the discussions in supervisions far more useful in terms of learning than the lectures, reading and essays.
There's a formula to that sort of essay writing and once you've cracked it, you can rattle them off in an hour or two once you've done the reading.