Holding plastic toy shovels and buckets, Mark Lewis and his son were ready to get serious on their beach vacation.

They built a huge mound of sand, poured water from the Atlantic Ocean over it, then jumped onto it and chipped away at it with shovels. The result was their first ambitious sand sculpture: a copy of Minas Tirith, a fortified city from “Lord of the Rings.”

Since that 2010 beach trip in Weymouth, England, Lewis — sometimes accompanied by his son Ethan — has improved. A lot.

He has made more than 200 sand sculptures, including ones of popular fictional characters — like SpongeBob SquarePants and Darth Vader — and items you might see every day — like an engagement ring and a Fanta can.

But it was a pair of roughly 3-foot-long Crocs he sculpted in May that put him on the map. While Lewis didn’t view the sculptures as his best work, beachgoers took photos standing in the oversize Crocs and posted them in a local Facebook group, giving Lewis a taste of fame in southern England. He gained hundreds of social media followers and was featured in the BBC.

Lewis, a part-time church minister, said he sculpts the enormous sand structures as a way to brighten someone’s day “when they stumble across something unexpected on the beach,” he told The Washington Post.

“It’s just nice to put a smile on somebody’s face,” said Lewis, 57, “and put a bit of joy into the world.”

The hobby began in the mid-2000s when Lewis and his sons, Ethan and Simeon, built sandcastles during beach trips. They decided to start making more complex sculptures and landed on Minas Tirith; they then started experimenting with new techniques in the following years.

In 2011, they constructed a copy of the Tower of Pisa. The next year, they made a head, a mermaid and a squid. In 2013, the family of “Star Wars” fans assembled R2-D2, a bird from Angry Birds, a dolphin and a Lego figure.

Groups of beachgoers sometimes watched Lewis sculpt, he said, and he would often give lessons to children who marveled at the figurines.

In the following years, Lewis made sculptures of Han Solo in carbon from “Star Wars: The Empire Strikes Back,” Maui and Moana from the movie “Moana,” and Hogwarts, the boarding school from “Harry Potter.”

Each sculpture takes one to eight hours, Lewis said.

He has honed his techniques over the years. Lewis, who took art classes in high school in Bristol, England, often draws the designs he wants to sculpt in a sketchbook. He sets up bamboo barriers and shovels sand inside. He then pours water in — from the ocean or a hose — and mixes the sand and water by shaking the barriers or jumping atop the sand to harden it.

He then turns to his tools, some of which he makes himself. Lewis removes metal strips from windscreen wiper blades, uses trowels to carve large shapes and palette knives to engrave small details. He creates circular shapes with flexible rulers, which he also uses to measure. Brushes allow him to flick off pieces of sand, and straws give him a narrow hole to blow away sand in small areas.

Lewis said he feels immersed while sculpting — a state of mind psychologists call “flow” — so his wife, Jane, will remind him to eat, drink water and go to the bathroom.

The tallest sculpture Lewis has built is a copy of the Saturn V rocket, which he and Ethan, now 27, made in July 2019 for the 50th anniversary of the Apollo 11 landing on the Moon. It was a few inches taller than Lewis and Ethan, who are each 6 feet tall.

But those ambitious projects don’t always work out. While many professional sand sculptors have indoor sandpits, Lewis has to factor in the sun, waves and the wind.

While building Orthanc, a “Lord of the Rings” tower, in July 2021, heavy winds blew the sculpture away before Lewis and Ethan could carve spikes on top. Lewis starts sculpting above where he expects the high-tide line to be, but in August 2022, he guessed wrong, and the waves destroyed his sandcastle before he got far.

Lewis doesn’t mind that his work is ephemeral — as long as he takes a photo of it before it’s gone. He often jumps on his finished sculptures instead of leaving their demise to nature or a beachgoer.

Still, when Lewis and Ethan constructed a lion in Weymouth in May 2024, they were ecstatic to find it was still standing when they returned the next day. That same year, Lewis and Ethan demonstrated how far they had come by assembling Minas Tirith — the same city they built in 2010 — with more detailed windows, doors and tower ridges.

With new social media followers who found him after seeing his Crocs sculpture, Lewis recently asked fans for suggestions of what he should build next. The list included flip-flops, an iPhone, a toaster, a kettle, and strawberries and cream, a staple dish at London’s Wimbledon tennis tournament.

Lewis quickly got started in the roughly 8-by-8-foot sandpit he built in his York, England, home’s backyard two years ago. He assembled strawberries and cream and a spoon in early July.

After taking photos and videos, Lewis demolished the sculpture by jumping on it in his blue Crocs — the ones he used as a model for his most famous creation — leaving the sandpit fresh for a new creation.