In Stornoway, the biggest town in Scotland's Outer Hebrides islands, a yellow van sits on a narrow, one-way street. The Gaelic word leabharlann is painted on the front, back and sides, with its English translation, "library," on the front and sides.

Driver Iain Mackenzie has loaded his books in the van, organized his customers' orders and is preparing for his last run of the week on the island of Lewis and Harris. The 16-year-old van runs three days a week, covering more than 800 miles of rugged roads to deliver books to more than 800 residents.

Mackenzie and fellow mobile librarian Steven Bryden, who handles the Harris part of the island route, have been driving the library van for seven and 13 years, respectively. They know their hundreds of customers so well that they've memorized their reading preferences and quirks.

Bryden knows to deliver audiobooks to Douglas Neal's front door because Neal is mostly housebound and appreciates the opportunity to socialize. Mackenzie knows that Donald John loves murder mysteries — and he knows to keep the van doors open when driving up to John's house, so John's dog won't chew on the rubber insulation that protrudes when the doors are closed.

The Outer Hebrides, also known as the Western Isles, began its mobile library service in 1952. The places it serves are home to Scotland's highest concentration of "very remote rural" residents. Stornoway has a population of 8,000, but 73% of the Hebridean population qualifies as very rural remote, defined as "areas with a population of less than 3,000 people, and with a drive time of over 60 minutes to a settlement of 10,000 or more."

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Off the coast of northwest Scotland, the Outer Hebrides encompass mountains and moorlands, rugged coasts and pristine, sandy beaches. The islands' scattered villages have grown quieter as people have moved away, in search of greater opportunity.

When the mobile libraries began operating three generations ago as a local council service, they were the main source of books for Outer Hebrides crofters — livestock and vegetable farmers who shared land spread out around the islands. Then, as now, residents had limited access to transport and the wider world.

"We couldn't afford to buy books and the books came in the [mobile] library and... wow," recalls Agnes Matheson, 77, who grew up in Lochs, on the Lewis part of the island just before it becomes Harris.

Even now, "The main thing is knowing that it's a lifeline to culture. That sounds awfully grand and overstated, but it's the truth," says Douglas Neal, 69, the housebound Harris resident who has audiobooks delivered to his door. He is disabled and relies on the service because getting to his local library is a physical hardship.

The mobile libraries also serve as a lifeline to other people. In an increasingly distant, digital age, the service has made a difference in declining communities whose residents seek personal contact. Without the mobile libraries, some residents would be more than an hour's drive from their nearest library branch. Others, even if living less than a mile away, would still be unable to visit because of physical hardships.

Mobile libraries remain integral to these communities. Visits by drivers like Mackenzie and Bryden are sometimes the only regular face-to-face contact customers can count on in any given week. "A man in the [Harris] bays once told me, 'The last person I saw was you,'" says Bryden.

As rural high streets — the centers of local businesses — begin to disappear, and schools, jobs and other opportunities have seeped away to large cities, villages across the isles are facing depopulation and a decrease in resources. A 2007 Outer Hebrides Migration Study reported a 43% population decline between 1901 and 2001, as well as a long-term decline in the number of women of childbearing age, resulting in more deaths than births each year. "The key drivers of population change are the limited job opportunities available," the study said.

And as the islands' populations have shrunk, services have declined. In more remote areas, when school is not in session, public transport is available only once a week. "The further away you get from the largest population, the less money they spend. We don't have services: [garbage collection] every fortnight, no street lights" and inadequate drainage that sometimes floods houses, says Susan MacVicar, a resident of Harris.

Despite frequent threats to slash its funding, the mobile library is one service that has remained. Last year, the local council voted down a proposed $231,000 cut for the vans. Still, there are worries about the mobile libraries' future.

"Though we have had a reprieve, it is likely that this might be the last decade of this kind of service," says senior librarian Kathleen Milne, referring to the arduous process it's taken to replace the existing, aging vans.

Library cutbacks have become an epidemic in Scotland, with 30 branch libraries closing in 2017 — double the number that had shut the year before, despite an increase in the number of library users in the same period. In the past four years, two libraries have closed in the Western Isles, with four remaining.

The Outer Hebrides originally had three library vans: two for Lewis and Harris, and one for North and South Uist. When the Lewis mobile library van broke down in 2015, the Harris vehicle began to serve both Lewis and Harris, but less frequently: customers now receive visits once every six weeks instead of every three. The van Mackenzie and Bryden share was due to be replaced six years ago.

Although most mobile library customers are elderly or disabled, or both, younger readers use the service as well. The mobile libraries function as a resource for primary schools and senior living centers, offering a regular rotation of reading materials.

While mobile library vans aren't unique to the Outer Hebrides and serve communities all around Scotland and the United Kingdom, the Leabharlannan nan Eilean Siar — Western Isles Libraries — provide something special: Gaelic-language resources to a region that is home to Scotland's highest density of Gaelic speakers.

Budget-saving proposals have offered to substitute the mobile libraries with online books and volunteer-run community hubs, but residents say these don't come close to the personal experience of physically choosing books, and none offered access to the limited Gaelic resources available.

For Annabel Mackinnon, a retired schoolteacher in her 70s, the mobile library provides Gaelic books that are not available on her e-reader. Born and raised in Uig, part of Lewis, she grew up speaking both Gaelic and English. Her mother, she says, believed "English was the passport" for opportunity.

Today, she rarely hears Gaelic. "In 2005, when I retired," she says, "I would go into the shops speaking Gaelic and they'd tell me, 'There's no use for speaking that anymore,' to which I was horrified. And carried on anyway."

Mackinnon writes a Gaelic article in every issue of the bimonthly Uig newsletter, and makes a point to borrow Gaelic books from the mobile service to continue her own practice.

Further north on the island, toward the community of Ness, Mairi Coxon, a mother of two, was also raised speaking Gaelic, but she isn't fluent in the written language. She can access Gaelic-language books online, but says the mobile service is especially helpful because it allows her to flip through the texts and confirm that they're within her reading level before she borrows them.

When the mobile library service was at risk of being cut, the Outer Hebrides communities rallied to save it. In December, the local council approved two new vans, one for Lewis and Harris and the other for North and South Uist.

It isn't clear when the replacement vans will be delivered. But for longtime drivers Mackenzie and Bryden, who have navigated their aging vehicles through the islands' rough roads and unpredictable weather — including gales and storms — the approval for replacement vans marks a victory. "There's a perception in [small villages] where everybody knows everybody, but it isn't always the case," says Bryden. "There are a lot of people on their own who are just missed. It's just keeping an eye out on people."

"If you don't keep fighting for your services, they'll just keep getting cut and cut," says Mackenzie. "And once they're gone, they won't come back."

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