My pick
My tip“An hour and a half from Palma; book an early slot online; there are many steps at the exit.”
Huge limestone caves with stalagmites and stalactites, ending at Lake Martel, one of the largest underground lakes in the world, where a concert is played from illuminated boats.
Moderate effort
Buses from Palma to Porto Cristo, or a car with parking nearby. Inside the cave, about 1.2 km on wet, slippery paths with many steps, especially on the way out; not suitable for wheelchairs or strollers. Book in advance. Café at the entrance.
Address
Ctra. de les Coves, s/n