During an exhibition of his work at CEPA Gallery four years ago, photographic artist Stephen Marc began exploring local sites on the Underground Railroad - the pre-Civil War network of safe houses where runaway slaves were concealed en route to freedom in Canada.

One of the first places he visited was Michigan Street Baptist Church, a legendary waystop in which bedraggled men, women and children, nearing the end of their treacherous flight from the South, hid in a cramped cellar before crossing the Niagara River in the dead of night. That day, and on subsequent visits, Marc shot many images for "Passages on the Underground Railroad," a book he hopes to publish in 2006.

He was back in the landmark church Tuesday, helping Bishop William H. Henderson prop up a ladder to explore what may well have been a second hiding place for slaves, in a recess above the choir loft. The crawl space went unnoticed for nearly 150 years before it was recently discovered by an electrician working in the building.

The moment coincided with Gov. George E. Pataki's announcement that the landmark brick church at 511 Michigan has been selected for a new statewide Underground Heritage Trail.

"Passages," a work-in-progress that will combine documentary-style color compositions of individuals; montages containing symbols, people and landscapes of the Underground Railroad; and a text still to be written, grew out of a discussion between the artist and CEPA Executive Director Lawrence Brose in 2000, while Marc was here for an exhibition of his complex montages titled "Soul Searching."

"I knew a little about the Underground Railroad - that Buffalo and Detroit were the major border crossings for slaves," said Marc, who has been given two shows at CEPA and one at El Museo Gallery. When Brose proposed that he return for a residency in 2002, Marc decided to delve further into the subject.

Poking his lens into secret hiding places like the basement of Michigan Street Baptist Church proved "so absolutely incredible, so profound, that I wanted to do something additional that addressed the Underground Railroad," he said.

He has since taken countless images - including 1,800 on a single trip to Mississippi - that he hopes to condense into a moving pictorial tribute to those who made the journey and people who helped them along the way. "Passages" will be published by the University Press of Mississippi.

An Arizona State University art professor who began taking pictures 31 years ago, Marc believes still photography, better than videotapes or movies, gives the viewer all the time he needs to contemplate an image's meaning.

Pataki said the state will provide a $1 million grant program to "enhance the interpretation and preservation of our many historic treasures" on the Underground Heritage Trail. The news was delivered to Sandy White of the Buffalo Niagara Freedom Station Coalition, a nonprofit group overseeing restoration of Michigan Street Baptist, which was started in 1845 and was the city's first black church.

e-mail: tbuckham@buffnews.com