While I was flirting with Shizuka, Doraemon had finished adjusting the underwater bicycles.
"Alright, everyone, check the screens on the front of the bikes; there's a navigation map of the ocean floor!"
"You can see your position and current depth."
"So, let's start our underwater journey!" Doraemon said, leading the way by riding his bike into the sea.
We all got on our bikes and followed behind Doraemon.
Seiko was scared at first, keeping her mouth tightly shut, but then she realized there was no need to worry; we could breathe freely underwater.
As the underwater bicycles moved away from land, the water gradually rose over our heads.
"It's just like on the surface," Seiko said in surprise, opening her mouth.
"Really! And we can hear sounds too!" Shizuka happily chatted with Seiko.
The ocean floor had colorful coral reefs and all kinds of fish swimming around.
"Woo-hoo!" Gian shouted excitedly like a gorilla.
"Strange, isn't the ocean floor supposed to be dark? Why is it so bright?" Suneo asked puzzled.
But he quickly realized it was a dumb question, since Doraemon had already explained it was the Adaptation Light.
"That's why I had you all use the Adaptation Light. See? It's just like being on land. Even at 10,000 meters deep, it'll be like under the sun," Doraemon said casually with a chuckle, repeating it.
"We're currently on the continental shelf, where the water depth is usually no more than 200 meters. It's mostly gentle slopes, so riding here is stable, and this is one of the prettier spots underwater," Doraemon explained while riding and teaching us.
As we kept riding forward, the surroundings changed slowly; the coral reefs and fish disappeared.
Suddenly, after a barren stretch, we arrived at a cliff edge on our underwater bicycles.
"It suddenly drops deep from here; what a steep cliff," Suneo said, looking at the underwater chasm in surprise.
"This is even more intense than in the mountains!" Gian couldn't help saying.
"That's why I said there are mountains in the sea!" Doraemon smiled.
Then Doraemon analyzed the chasm: "This is the continental slope, leading straight to the deep ocean floor, several kilometers down."
With a mischievous grin, Doraemon said, "Let's rush down all at once!"
He rode his underwater bicycle right toward the cliff.
We were all shocked.
But then we saw Doraemon's bike sticking to the cliff edge, like on flat ground.
"Don't worry, everyone; you won't fall. The bikes will help keep you balanced," Doraemon called from below.
We stopped hesitating and rode our bikes down, following Doraemon.
"Awesome! It's like a roller coaster!" Gian felt the thrilling speed of riding down.
"Is that the Kuroshio Current?" Suneo pointed at the fish school ahead and said.
Schools of bonito swam by, making the descent even more special.
As the bumps lessened, Doraemon reminded us from ahead, "Everyone, the slope is easing up; we'll reach the bottom soon!"
Once we hit flat ground at the end of the slope, we all started looking around.
"Wow! Look at that ship up there; a hundreds-of-thousands-ton cruise liner looks like a leaf floating above us," Seiko suddenly looked up and pointed at the ship on the surface in amazement.
"Our current position is over 3,400 meters below the surface!" Doraemon reported a surprising number.
"3,400 meters! So deep! But it seems like there's nothing here!" Suneo looked at the empty ocean floor and felt bored.
"There should be some deep-sea fish; let's keep going and see!" Doraemon said, urging us to continue riding.
But in the deep sea, riding along felt like being in a desert—sand everywhere, endless.
It looked lifeless and boring.
Seeing everyone like this, Doraemon knew we needed to hurry.
"Alright, this is a plain; it's perfect for speeding up."
He pressed buttons on both sides of his underwater bicycle's handlebars.
"Everyone, just press these buttons, and the bike will go automatically. The handles adjust speed, and the screen shows real-time speed."
As Doraemon pressed the buttons, his bike accelerated forward without pedaling.
This turned the bicycle into an electric one?
I was surprised.
"Doraemon, why didn't you say so earlier? We were pedaling so hard before," Suneo complained.
"This way, you could experience the underwater bike off-roading first?" Doraemon said awkwardly.
But we didn't dwell on it and switched our bikes to auto mode.
As everyone pressed the buttons, all the bikes sped up several times.
Twisting the handles to max, the speed was almost like a car's.
At that speed, we quickly left the desert area behind.
"Doraemon, where are we going?" Shizuka asked from behind.
"See the screens on your bikes? We've just crossed the Japan Trench, and now we're heading to where there are mountains, around Hawaii."
"Huh? Hawaii?"
We didn't expect a place that requires a plane to reach would be so quick underwater.
After a while...
"Everyone, look, look! See the mountains," Doraemon pointed ahead to the emerging peaks.
"This is the mid-Pacific seamounts; we're near Hawaii now."
"They're towering from the ocean floor, about 1,000 meters high!"
Doraemon continued his explanations.
"Wow! Since there's no clouds underwater, these mountains look so clear!" Seiko said in amazement, looking at the sharp peaks ahead.
"Originally, this place is pitch black, nothing visible; it's all thanks to the Adaptation Light," I praised Doraemon's gadget endlessly.
Our bikes rode through the underwater mountains and valleys, but being underwater, these peaks had no creatures or trees; everything was utterly silent.
Like a forbidden zone for life.