The fastest-growing group of Maine tourists may be entering the state by a dock, not a highway. The cruise ship business, over the last 10 years, has given coastal communities a substantial influx of cash spent in restaurants, shops, galleries and boutiques. The only downside is that lodging establishments don’t see increased patronage, but it’s not hard to imagine a first-time visitor coming to Camden or Castine by ship, then being smitten by a town’s charms and returning for a week stay the next year.

While Bar Harbor is the most visible winner, with an estimated 150,000 passengers expected to stroll the town’s sidewalks between May and October of this year, there is another, rapidly expanding segment of the cruise ship business that is proving a boon for other Maine towns. Small cruise vessels from American Cruise Lines began visiting the Maine coast and inland river ports like Bangor several years ago. The ships offer two trip packages that stop in Maine. One eight-day itinerary includes stops in Bucksport, Bar Harbor, Rockland, Castine, Camden, Belfast and Bangor. A 10-day tour beginning in Providence, R.I., hits Portland, Boothbay Harbor, Bar Harbor, Rockland, Camden, Belfast and Bangor.

Because the vessels carry fewer than 100 passengers, their calls at small ports like Belfast, Bucksport and Boothbay Harbor do not overwhelm the harbor facilities or the downtowns.

Bob Hastings, executive director and CEO of the Rockland-based Penobscot Bay Regional Chamber of Commerce, has had a front-row seat to watch the growth in the small cruise ship business, seeing 28 port calls this year — although he’s been doing anything but sitting and watching.

Mr. Hastings is actively courting other cruise lines and is expecting visits from the much larger Royal Caribbean line, whose vessels carry 3,100 passengers and crews of 800 or more. Business owners are given a heads-up on the visits, the lively downtown is spiffed up, and the chamber even plans to have docents available on the sidewalks to help steer the visitors around town.

The extra attention pays off, Mr. Hastings believes. With relatively few cruise ship businesses operating, he says executives often compare notes about which ports are worth adding to itineraries.

Mr. Hastings notes that passage on the smaller vessels actually costs more than on the big ships — as much as $5,000 to $6,000 for a week. These passengers spend, on average, $300 per person in each town they visit; the big ship passenger spends about $100 per day. The small cruise ship visitors especially like Rockland, Mr. Hastings says, with its boutiques and art galleries.

Next on his to-do list is having Rockland serve as home port for one or more of the vessels. That would mean the ship would be cleaned, garbage would be removed, the ship would be supplied with groceries, lobster and the like, all by local businesses, in between voyages.

“It couldn’t be a better fit for developing the tourist industry,” he says. Tourism officials should work to keep the gangplank out for more ships.