I had the same reaction when I saw this article on CNN a week ago. A little more exciting than "lost drain pipe discovered under Utah couples' home", but not by a whole lot!

At least the title was descriptive and not "You won't believe what was discovered under Sforza Castle".

From the title I wasn't sure if they were even found

The tunnels they found are definitely plural though, only the connection to the sketches seems a bit tenuous.

> It features a well-known underground passageway that runs along the perimeter of the castle’s moat and is accessible to tourists. But to the researchers’ surprise, their survey revealed a second secret tunnel that experts had only hypothesized about for years.

The second tunnel runs parallel to the first one, about 1 meter (3 feet) beneath the surface. [...]

The researchers also uncovered other tunnels [...] including one that heads in the direction of the Basilica of Santa Maria delle Grazie, the resting place of the wife of Duke Ludovico Sforza.