I have never taken a rollercoaster in my 13 year old life (i'm not a coward.. it's only that just looking at them makes me feel sick), but at my local amusement park, there is kind of an easier rollercoaster called SuperSplash, as the name tells you, it ends in water, but at the start, it's just like 0:43-1:05, just that it takes a longer time, and looking out of it just.. AGH! My stomach! And when the upwards hill is done, it suddenly goes a little downhill that makes you feel like you're dropping from that insane height... Ack! But at least it's not as crazy as the one in the video. And the downhill that leads down to the water makes me weightless

But what's really not fun is that there is a wall of stone at the end of where it's downhill, I know it's safe and that i'm only 1,60 cm yet, but I always get a false sensation of that i'm going to bang my head into it.. OUCH!
And then we go through a dark cave, and in the end of it -
SPLASH.
That's what roller coasters are all about! Experiencing what would normally be too frightening to experience.
Every year, amusement parks spend millions to keep the rides safe for guests. I'm 6'2'', and lots of local theme-parks around here have tunnels on their rides. Most of the time; the clearance is actually measured in feet; not inches. One local wooden coaster actually has the train running past a rock-face at 40 miles an hour!
At that speed, the sensation makes you think that it's MUCH closer to that wall. Yet on the 200+ times I've ridden it; Never once have I come close to grabbing any of the branches, bushes, shrubbery, or any sort of scenic piece near the ride. (It's built on the side of a Mountain with much greenery surrounding the ride, never mind the aforementioned rock faces).
You're still young though; and roller coasters aren't for everyone. I rode my first real one when I was 10; and I haven't stopped in almost 10 years! I've been on roller coasters of all shapes and sizes. Be they small, "kiddy" coasters at local fairs; or steel behemoths that have won international awards on many different years, like
Superman: Ride of Steel Er... Bizzaro, at Six Flags New England.
And to comment on what you said about the video... This particular ride is considered very tame nowadays. That very same park has roller coasters in which you're hanging below the track, going through inversions that are much larger, going at faster speeds (Raptor); One that has you STANDING up in the train, going through those same inversions and speeds as Raptor (Named Mantis)... And one that, at one point, held the record for the World's Tallest and Fastest roller coaster... At an amazing 420 feet tall and 120mph! Did I mention it launches you to that speed in 3 seconds? The entire ride length is 17 seconds from launch to brake. Top Thrill Dragster earns its name.
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