A finely-detailed sandcastle, complete with turrets, towers and stony arches, is bringing a touch of the beach to the financial district.

With no blueprint or plan, Michael Long sculpted the 17-foot-high castle out of 55 tons of sand. It took him 14 days.

"You start with one spire ... and then let it bleed out," Long said. "One element of the castle sort of leads to the other."

Long, who has been building castles for more than 12 years, says he does it simply because he enjoys it — and because he likes the effect his work has on others.

Many passersby were amazed. Jason Wade from Long Island said the sandcastle blew his mind. "I've never seen a sandcastle in my life that was real...it's beautiful," Wade said. "The details to me are very attractive."

Long said he believes that people are enchanted by sandcastles because of the underlying knowledge that they are temporary. "It's a step beyond fantasy," Long said.

The castle, on Water Street in front of One New York Plaza, is protected from the elements by a mixture of water and water-based wood glue applied to the sand.

It was built as a part of the city’s Water Street POPS programming and South Street Seaport’s summer programming called SEE/CHANGE and will be on display until August 12.