My tour started met at 1430. We were kitted out by 1500 and the tour lasted for approximately 2hrs 30mins.

As the previous TripAdvisor said: If you're located near the river, then the extensive public transport system will readily get you there (we were there for a month, and each of us bought a 1 month pass- then jumped on every train, tram, bus, metro or ferry; without any question). We stayed in a AirBnB, near the Budapest 'Eye' (a huge white ferris-wheel type structure), and it was perfect (again, cheaper when we booked for the full month). The caves were an absolute delight, quite unique to our previous experience. We did a 2hour tour. The recommended age range was 14-55, but my boy & I did it easily (I'm 63, and he was 10- but both moderately fit. Neither of us play competitive sport, but we cycle & walk regularly, and eat healthy). My 10yr old felt it was a snack to do, and he'd immediately follow on the heals of the guide, through every portion of the course. For me, there were some challenging moments, but the guide was very helpful, informative & quite funny. Neither of us had ever done caving before, but we heard such good reports, so we did it. I'm so glad we did. We highly recommend it. (Back in Australia, my boy often proudly wears his "Caving under Budapest" t-shirt).

I've previously posted a report on our experience. I thought that the 14-55 range applied to the 2 hour tour (but I may not have the details clear in my memory). As for the 2 hour tour, I would heartily recommend that you & your fit 10 yr old, 'go-for-it'. My boy is a bit taller than the average (australian) 10 yo boy, & he's confident. So he & I simply presented to the ticket person, bought tickets & went along. There were no questions asked. (I was 63 at the time). They supplied a 'jump-suit' to wear over your clothes, which covered us adequately. Although the caves are 10-15oC, you certainly won't be cold, coz your increased activity will generate internal heat. Consider whether you wish to take a mobile (for photos) or not. No doubt photos of you in the caves would be great, but you probably won't get 'post card' quality (coz the team is on the go). And the risk of getting very fine dust on (or in) your phone, may deter you from taking it (they warn you of this). For us, now we're back home: we took no photos; & so we just love to relate the story, my boy wears his "Caving Under Budapest" shirt everywhere; & for our slide night we included some pics that I grabbed from their publicity on the web. Everyone (back home) is more than happy with that, coz they know you're with a team of tourists (maybe 5-10), so shots of 'others' in tight spots seems normal, & it still brings "ooohs" from your "holiday snap-shot" watching audience (coz they know that you too did those tight spots).