She was walking down the street in Monrovia, Liberia, feeling angry.

Then she and her friends heard singing - gospel music.

And they followed the sound right into a church.

"It sounded like a Baptist church choir, just like home," remembers Carolyn Stallworth, 65, of Rochester Hills, Mich., of that trip in 1988. She and her friends, all Spelman College alumni, were furious because they'd had to surrender their passports upon arrival in the African dictatorship. But when they heard the choir practicing at the Providence Baptist Church, their mood lightened.

"The next morning, we went to church there," she says. "Not only did they sing the gospel spirituals, but the United States Marine Band also played there, and the U.S. ambassador was there.

"Hearing those spirituals on the street that day, just standing outside, that was an amazing experience."

Some travelers take mission trips. Some take journeys of faith. Some take architecture tours of world churches.

But sometimes, regular people on vacation just happen to decide to attend a religious service - sometimes not even of their own faith - and it sticks with them forever.

"I think that when you travel, the very act of being taken out of your own environment opens you to new experiences. Somebody said, 'We go through life sightless among miracles.' And in part, that is because in the routine of our lives we stop seeing what is going on around us," says Stuart Matlins, editor of How to Be a Perfect Stranger (Sky Light Paths, Fifth Edition, $19.99) a guide to navigating religious services of all types. "When you are in a foreign or different environment, suddenly all your senses are heightened. You see the unusualness of life. It's not unlike witnessing miracles."

Matlins is Jewish, but he has attended many services around the world, from cathedrals in Frankfurt and Barcelona to a mosque in Pakistan and a synagogue in Krakow.

" 'Sit in the back' is really the best advice for anyone going to any religious service with which they are unfamiliar," he says. "In every circumstance, sit in the back, and you can't go wrong."

It takes a leap of faith to attend a religious service that is not your own. Even services of one's own faith can have twists.

But often, the experience is so vivid that it sticks with travelers.

Once, far from home and near Denali National Park in Alaska, Dennis Lakomy and his wife sought a church service - and ended up at a tiny Catholic chapel with 14 parishioners and no regular priest.

"It looked like a small home or a large living room, no pews, no anything," recalls Lakomy, 60, of Lake Orion, Mich. "They had a visiting priest who would come every once in a while, but he wasn't available every Sunday, so the day we went, the parishioners held a service on their own and distributed communion. There was a guitar player, and we were able to stay after and just talk to the members. They recognized we were from out of town. That was in August 1990, but it stuck with me so much."

For Richard Shook of Bay City, Mich., the Mass he went to in Xi'an, China - in Chinese - was as impressive as seeing Xi'an's famous terra cotta warriors.

The doors remained open during the February service "so everyone remained in their heavy coats - even the priests wore them under their vestments," says Shook, 70. "The church seated maybe 250 people and was full a half-hour before Mass started - and as people continued to arrive, they brought out little blue plastic stools to fill every available space."

And Pat Andrews, 75, of Trenton, Mich., vividly remembers attending a church in London that was across the street from a pub.

"The service was interrupted multiple times by a woman carrying a small barking dog. It was obvious she had been imbibing most of that day. Down the aisle she would come, and out the door she would be escorted by the priest, only to return again and again," she says.

Why are these small details - a blue stool, a barking dog, a guitar - etched so clearly in travelers' memories? David Crumm, editor of and a former religion writer for the Detroit Free Press, believes that attending religious services while on trips lets travelers connect with others at a more visceral level beneath the tourist veneer.

"People travel widely - then never actually engage with people," he says. "One way to authentically engage is to go to churches or religious services. I've done it throughout my life."

Suehaila Amen, 33, of Dearborn, Mich., believes the same thing. She recently was in Boca Raton, Fla., and attended services at two mosques.

"I attended two separate services, one conservative and one liberal," she says. "At the liberal mosque, I was welcomed, even though I walked in the wrong door, the men's entrance. Everybody was extremely friendly. . . . Then I went down the street to the very beautiful conservative mosque. It was more like, 'She's a new face; we don't know who she is.' They had people protesting outside the mosque." Once she was inside, "I found it to be a very warm experience."

Still, she fretted she might make a mistake in the prayers, that her arm placement might vary from what others practiced.

"I was worried that they might notice I did things differently than they did," she says. "My friend said, 'No, they won't even look at you.'" And nobody did - except later, when they recognized Amen as a former cast member of the All-American Muslim reality show on TLC.

Ann Langford of Howell, Mich., was humbled while visiting New York when she decided to attend Times Square Church, which has 8,000 members.

"Housed in a former Broadway theater, the congregation captured the true spirit of New York," she recalls. "The volume of the singing matched many rock concerts I've been to, and the Christian testimony made our eyes well up.

"It was literally the highlight of our weekend in the city."

Tips for Visiting Religions

The guidebook How to be a Perfect Stranger, as editor Stuart Matlins puts it, "equips each of us to enter into the religious realm of our neighbors." The guide is not theological, but practical.

Divided into chapters for each religion - and including helpful information for attending a wedding, baptism, or funeral in each faith - this guide is helpful for curious travelers who don't want to make a spectacle of themselves. Some of its advice:

Question: Where should guests sit in a Buddhist temple?

Answer: If there is seated meditation, a guest will be directed to a meditation cushion.

Q: Should non-Catholics take communion at a Catholic Church?

A: No.

Q: What books are used during a Methodist service?

A: The United Methodist hymnal and the Bible.

Q: What is a Sikh manji sahib?

A: A platform covered with ornate cloths that holds the sacred writings at the front of the room.