While the Benagil sea caves in Lagoa were once undoubtedly stunning but their popularity has led to dangerous conditions, ecological damage and overcrowding. The government has started an emergency process to save the caves, and tourists are asked to do the right thing and look for alternatives. So yes,  there are several other beautiful coastal destinations and sea caves to explore in Portugal. Here are some good alternatives, some not far away!

Ponta da Piedade, Lagos: Ponta da Piedade is famous for its dramatic cliffs, rock formations, and sea caves. You can explore these caves by taking a boat tour from Lagos.

Grutas da Moeda, Fátima: These caves are inland, near the town of Fátima, and are known for their stunning underground formations, including stalactites and stalagmites.

Arrábida Natural Park, Setúbal: This area is known for its rugged coastline and hidden caves. Praia dos Coelhos and Praia dos Galápos are two beaches where you can find beautiful sea caves.

São Vicente Caves and Volcanism Centre, Madeira: While not sea caves, these lava caves on the island of Madeira offer a unique underground experience where you can learn about volcanic activity and explore intriguing tunnels.

Berlenga Island, Peniche: Off the coast of Peniche, Berlenga Island features striking cliffs and sea caves, such as the Furna do Rei, which can be explored by boat or kayak.

Cabo Espichel, Sesimbra: This area has impressive cliffs, grottoes, and sea caves that can be explored on boat tours or by hiking along the cliffs.

Ponta de São Lourenço, Madeira: This eastern tip of Madeira offers stunning coastal views, including cliffs and caves, as well as a unique landscape that contrasts with the rest of the island.

One other great alternative,

Porto Covo is a beautiful coastal town located on the Alentejo's Costa Vicentina of Portugal, known for its stunning beaches and picturesque coastline. 

Porto Covo and the surrounding areas are known for their rugged cliffs and rocky coastline, which offers natural sea caves and grottoes. Some popular spots to explore sea caves and rock formations in the vicinity of Porto Covo include:

Ilha do Pessegueiro: This small island is just off the coast of Porto Covo and is known for its caves and underwater grottoes. You can take a boat tour to explore the caves around the island.

Praia dos Buizinhos: This beach is known for its rocky formations and sea caves. It's a popular spot for snorkeling and exploring the underwater caves.

Praia da Samoqueira: Another beach near Porto Covo that features unique rock formations and caves. You can explore these formations at low tide.

Praia do Cerro da Águia: This beach is a bit further south of Porto Covo and also has some interesting rock formations and caves along its coastline.

When exploring sea caves, it's essential to prioritize safety. Check the tide schedules, be cautious of changing sea conditions, and consider joining a guided tour if you're not familiar with the area. Additionally, always respect the natural environment and local regulations when visiting these beautiful coastal areas. And, help save Benagil, and make other plans.