Mount Snowdon, not sure how tall that is?
I've been up various mountains in Peru when hiking to Macchu Picchu. I went with Scope and we didn't do the Inca Trail but rather an alternative route where we didn't see any other foreigners until the last day when we joined up with the Inca Trail. I'm guessing that of them all, perhaps Wayna Picchu (one spelling, there are various!) might not have been the tallest - coped this from Wikepedia:
Huayna Picchu is about 2,720 metres (8,920 ft) above sea level, or about 360 metres (1,180 ft) higher than Machu Picchu. BUT it certainly was the steepest climb we did! I don't know whether I had just adjusted to the altitude by then or whether some of the other peaks we climbed were taller but it wasn't the worst one for breathing at any rate.
All I know for sure is that the photograph I have of my friend and I sitting right at the very top, with nothing behind our backs but that VERY long drop, is enough to make DH turn green

The ascent was tricky but the descent was really terrifying - an inch at a time down Inca steps worn down so smooth that they were like trying to scrabble on your hands and knees down a slide of horizontal drainpipes

On our way up we met one poor young man in our group - one of the fittest in fact - coming down. That was NOT good, as he was ashen faced. There was no way we could turn around either? Glad I made it and what an experience.