There’s more than high school team rivalry that keeps people on the Vineyard and Nantucket braced apart from one another. Unless you’re one of the lucky wanderers who has traveled back and forth with enough frequency to consider both Islands home, a chance visit to the Island You Don’t Know could make you almost-imperceptibly-but-ever-so-slightly uneasy.

It’s not explainable. It’s not rational. But it’s real.

“A nice place to visit, but you wouldn’t want to live there,” said a chuckling Nantucketer as he exited the high-speed Hy Line ferry, returning from his Sunday overnight on Martha’s Vineyard. The two dozen or so Vineyarders lined up for the trip home gave out an appreciative laugh. The man’s sentiments so mirrored our own there was no way we could take offense. And we knew by the smiles wreathing our faces, that a jolly good time had been had by all, even after a night spent on the wrong island.

The luxe exchange program was the brainchild of Vineyard businessman Mark Snider, owner of Winnetu Oceanside Resort on the sands of Katama, in operation since the mid-1990s.

Mr. Snider is immune to the resistance of one set of Islanders to another. He recently determined that a hotel as plush and welcoming and historically dazzling as the original Nantucket Hotel of 1890 would rise again along Breeze Point. Now that he oversees a resort on each Island, Mr. Snider is eager for others to embrace a holiday version of Rodney King’s sentiment: “Why can’t we all just learn to get along?” [And enjoy each other’s adorable downtowns. And unspoiled beaches. And views of ragged, overlapping tides dramatic enough to make Herman Melville rise from the dead and write a new Moby Dick — this one set in Oak Bluffs.]

The Two Hotels Two Islands package continues through Oct. 24, with more jaunts envisioned for the popular Christmas Stroll on Nantucket and Christmas in Edgartown on the Vineyard. The best part about this two-stepping Island trip is that all logistics — the little hobgoblins of vacations — are taken care of by hotel staff on both Islands.

On our side of the pond on Sunday, in the early afternoon, some 25 Vineyarders assembled at the Hy Line wharf. Most of the friends and neighbors I polled had specific reasons for visiting Nantucket. Ellie and Red Bates had married there some 22 years before. Lynda Hathaway and her significant other, Jimmy LeBarre, have been sailing to Nantucket for the 19 years they’ve been a couple. Greer Boyle, co-owner with Christian Thornton of Atria and Hooked said: “I’m just a foodie, that’s why I come to Nantucket. The food is even better over there.”

My reply: “That’s saying a lot, coming from you!”

She was also set to enjoy a girls night out with half a dozen of her Vineyard friends. Later I caught sight of them at the Nantucket Hotel where they sat around an open fire on the grand old Victorian porch. They retired to their rooms to engage in a take-no-prisoners pillow fight, then changed and came down for a formal dinner in the high-ceiling pale-ash-tinted walls of the restaurant.

The rooms are well-spaced, light and bright, with those new smells that rise from freshly milled wood and new textiles. Each floor has a study with club chairs, sofas and a computer with high-speed hookup. On the ground floor, a huge pool adorns the courtyard. Below the lobby, a fitness center, billiard room, guest laundry and various other amentities greet the weary traveler, so far, so very far from her own Island.

On Monday morning a fresh breeze shook the turning leaves of oaks and shrubs; it was the first day of October. The Vineyard visitors could not ply those old cobblestone streets in downtown Nantucket fast enough as we wove in and out of each other’s way across the village. We came up against a parallel universe here — the weathered gray shingles, old rooflines, austere facades set against high church steeples and infinite sweeping views down one jetty and wharf after the next. We felt we could be home and yet nothing here was identifiable! Hence the mad dash around town all through the morning and into the early afternoon to establish some fixed points in our minds.

When it came time to leave, the classy hotel staff had our bags packed onto jitneys and they packed us onto them as well, unless we preferred to make one last cobblestone dash, which most of us did.

On the trip back, the captain warned of a bumpy ride and advised staying in our seats. Nantucketers, if they wish to get personal, remind Vineyarders that we can barely call ourselves Islanders, living as we do some seven safe miles from Cape Cod. And you know what? Slugging through the high seas from south by southeast to north by northwest, with waves bashing over the second story of the high-speed ferry, I think we can comfortably hand off that claim to fame broached by our brothers and sisters from the smaller, farther island: You are made of sterner stuff.

But our football team usually whomps yours.

For more information about specials involving hotel stays on the Vineyard and Nantucket through Oct. 21, call 508-228-4747 or go to thenantuckethotel.com.