There are SO many variables here. Stroller or no? Weather? Are they normally early risers or late night kids? Do they normally nap? How long is the trip?
If it's a short trip, then you may get away with more. They'll be excited and may have some of that excitement energy. So you could probably push farther than a "normal" day at home. But if it's a week or longer, then trying to do that may result in them crashing and burning by day 3 or 4. And again, things like stroller/weather/etc...will come into play.
When our kids were that age, we had a stroller 100% of the time. Even with that, if we were there around park open, usually we were done by early to mid-afternoon. Even now, with them being 13, 10, 10 we don't do commando days. If we're in the parks at 9:15am, we're usually done by 4pm. We may go back at night for a bit in that situation, but definitely not daily.