Sometimes it takes a trip off-Island to appreciate the cost and persistence it has taken to preserve the unspoiled stretches of open space on the Vineyard that we admire and too often take for granted. This week, after nearly a generation of grinding court cases, Island leaders won a final legal showdown in effort to save much of Moshup Trail in Aquinnah from development, when the United States Supreme Court declined to step in.

For the past twenty years, the town of Aquinnah, the Vineyard Conservation Society and a group of private landowners have been defending lawsuits brought by Belmont developer James Decoulos, who wanted to establish legal access to a set of landlocked parcels he owns off the trail. The issues of law in the case were twisty and arcane but the implications were writ large: if Mr. Decoulos had prevailed it could have had far-reaching effects on land titles throughout Aquinnah.

The cases were argued as far as the Massachusetts Supreme Judicial Court, which ruled last year that the Decoulos land had no legal access. The last legal recourse for plaintiffs was petition to the nation’s highest court.

Mr. Decoulos has said he intends to continue his fight for what he believes are his constitutional property rights, although there appear no obvious further legal avenues for him to pursue.

Leaders at the Vineyard Conservation Society, which for the past two decades has led the broad-based effort to protect the Moshup Trail heathlands, are hopeful they can now turn their efforts to long-term preservation.

To be sure, everywhere there is attractive land and lovely vistas there will be pressure to build homes and resorts so people can enjoy them. The mainland is filled with examples of once-pristine settings where the impulse to build went unchallenged.

On the Vineyard, there is a long tradition of pushing back successfully against those who have tried to develop large swaths of property, the resistance played out in courtrooms from Edgartown to Boston. In 1976, Island Properties was the first case to test the powers of the Martha’s Vineyard Commission. In 1993, the developers of Herring Creek Farm challenged three-acre zoning in the rural coastal perimeters of Edgartown, a case that lasted four years and went all the way to the state Supreme Judicial Court. In 2002, the developer of the Southern Woodlands golf course in Oak Bluffs sued the Martha’s Vineyard Commission in an attempt to strip the commission of its power to review affordable housing projects under Chapter 40B of state law.

In all these cases, the cause of conservation prevailed.

Not every acre of land on the Vineyard must be kept from development, of course, but Island leaders are right to keep challenging those who would domesticate the wildness we cherish.

The Moshup Trail heathlands remain a rare place where endangered orchids bloom in the spring. The trail itself is named for a figure in Wampanoag mythology. Children on Martha’s Vineyard know the story: according to one version of the legend, the giant Moshup emptied sand from his moccasins, forming the two Islands.

And when the fog rolls in, well, that’s just Moshup, smoking his pipe.