The Hardy boys knew that the Shore Road bluffs, in certain places, contained caves and passages, some of which had never been entered. Although like most Bayport boys, they had done a certain amount of exploring along the beach, they had never heard of the existence of this underground labyrinth. It seemed strange to them that so elaborate a series of caves had never been explored and their existence was comparatively unknown.
"Wait until Bayport hears of this!" Joe said. "Let's get out of here and hurry back to town."
"I suppose we should," Frank admitted. "I'd like to know where those men went."
"If we go any farther they may catch us, and then we'd be out of luck."
"But if we start back to town we'll have to walk, and they might all clear out in the meantime. It would be a few hours before we could get back here with the police."
"We'd have the satisfaction of recovering the cars, anyway," Joe pointed out. "I believe in playing safe."
"I'd like the satisfaction of rounding up this gang as well."
Frank advanced toward the opening at the far side of the cave.
"I think I'll just poke along in here a little way and see where it leads," he said.
Joe was dubious. He was of a more cautious nature than his brother, and was satisfied to let well enough alone. They had found the missing cars. This alone was sufficient, he reasoned. Having come this far without mishap he did not like to risk spoiling their success. However, he followed Frank into the tunnel.