🎄Underground (15 book series)

 Looking at the map that the lawyer was showing me, I asked, "This is all mine?"

He chuckled and said, "Crazy, I know, but your grandfather was insistent about it."

"How many miles of tunnel?" I asked.

"There are fourteen miles of tunnel and 20 areas in the fourteen miles," He said. "Basically, you own your own underground city."

"Underground city," I said. "What about the land above the tunnels?"

"You own that as well," He said. "There is also an underwater aquifer and generators that run from the currents of the water from the underwater streams there are as well."

"I will say again," I said. "This is crazy. How did my Grandfather hide this from everyone?"

"Do you remember when your Grandfather went fishing, hunting and camping?" He asked.

"Oh my," I said. "Yes, I do."

"That is your answer," He said. "The base of the underground is done. Now you get to continue with everything out."

14 miles of tunnel. 20 areas