The grass is greener on the other side of the Pier 6 Dog Run at Brooklyn Bridge Park, according to some dog owners.

That's because the run is made out of gravel.

"It's messy," said one dog owner at the park Thursday. "It's basically just rocks covered in dirt. Great if there's something slightly less dusty."

Others said the rocks were sharp and could hurt dogs' feet.

They are asking park officials to consider replacing the gravel with Astro Turf, special turf for dogs known as K9 Grass -- or even real grass.

Officials said they specifically avoided K9 Grass because it has no track record of use in highly-trafficked dog runs in the city. They also said K9 Grass had "extremely labor-intensive" maintenance requirements.