Hawaii is small enough that almost anywhere you park your SUV, you’re atop a historic site. Keeping track of what’s actually historic and what isn’t is the role of the National Register of Historic Places, a branch of the National Park Service. Is that pile of rubble over there a famous historic site, or is it just where Junior Boy dumped his rubbish? The register can tell you, courtesy its websites and links through Wikipedia.

However, some sites aren’t as well documented as others, and the "wiki" part of Wikipedia depends on public input. Joel Bradshaw and wife Jean Kirschenmann have become obsessed with documenting Hawaii’s historic places, uploading fresh information and photographs to the register’s listings as often as they can, with images residing on Flickr.com for anyone to enjoy.

Bradshaw, journals editor at University of Hawaii Press, said a Honolulu Star-Bulletin series on historic structures on Oahu and subsequent walking tours gave the couple the preservation bug.

"Our original goal was to make our recreational walks more varied and interesting by aiming for sites we could photograph to illustrate each of the items on the Hawaii NRHP listings in Wikipedia," said Bradshaw. "There were very few images in those listings. By now we’ve been able to supply photos for most of the listings for Oahu, Kauai and Maui, and learned a whole lot of fascinating local history in the process.

"I haven’t been able to resist creating or expanding Wikipedia articles when we find good documentation about the properties that pique our interest. The more we find out, the more we want to know."

According to Bradshaw, Wikipedia is conducting a "rigorous campaign" for contributors to provide citations. "There’s also a lot of editorial collaboration and oversight, occasionally irritating but often very helpful. Most of my contributions fall within the scope of two WikiProjects: WP NRHP and WP Hawaii," he said.

"The problem is that the sources we cite often contain errors — NRHP nomination forms, newspaper articles and even books by prominent architects who misremember names and dates. It requires a skeptical approach.

"A lot of feedback comes from fellow Wikipedia project team members. We have often been asked to take photographs for other people’s Wiki articles, and sometimes I’ve found someone else has already created an article that I was planning to do myself."

Their vacations are now structured around this hobby. They went to Kauai last Thanksgiving, and when Kirschenmann, a professor at Hawaii Pacific University, was at a Boston conference during spring break, Bradshaw drove around Maui finding sites around Wailuku, Lahaina and Upcountry. "I actually stayed at a B&B listed on the National Register, the Frank and Theresa Gomes House in Makawao. We’ll fill in some more pukas, especially around the Hana side, the next time we visit Maui."

Their current neighbor island goal is Lanai to document the Kaunolu Village site and photograph old Lanai City "before it gets torn down and redeveloped."

Most historic sites in Hawaii, it turns out, are not public property. "Public properties on the register tend to be better maintained than those that are not. Just compare the beautiful older buildings of McKinley High, Central Middle or Wailuku Elementary with those of most other public schools in the state," Bradshaw said.

"Homes on the register get property tax breaks, but commercial properties do not, as far as I know. And historic preservationists have sometimes put commercially owned properties on the register specifically to prevent the owners from destroying them. The landowners of Kualoa Ranch, Molii Fishpond and perhaps Kahaluu Fishpond seem to have done better by this than those of the Kahaluu Taro Lo’i or Kawa’ewa’e Heiau, which seem pretty badly overgrown."

A place on the National Register is no guarantee of survival. The Alexander Young Building, the Aiea Sugar Mill, the Kawailoa Ryusenji Temple and the Lishman Building in Makiki Park, for example, were still on the register even though they had been demolished. The Bradshaws, working through WikiProject NRHP, provided the Park Service with documentation showing the sites were long gone, although some remain on the register anyway.

"I think we all owe a debt to the civic-minded volunteers who help preserve and interpret such sites: local architects who organize the downtown walking tours every spring, the gracious ladies of Manoa who organize the historic homes walking tours every other year, various hula halau who have adopted many of the historic heiau — hell, even news reporters who compile articles about local history and make them freely available online," he said.

Because sites have to be at least a half-century old to be added to the register, the kingdom and the territory eras are well represented compared with the time of statehood. Hawaiian prehistory is underrepresented because many of the sites have simply disappeared, and residential properties on the register showcase the wealthy.

"Kings, queens, Castles, Cookes and Canavarros, people who could afford to build fine houses of lasting architectural interest," said Bradshaw. "I wonder if any of Genshiro Kawamoto’s Kahala mansions will make it onto the National Register 50 years from now?"

Bradshaw’s Flickr site blossomed in 2006 during a flower photography sojourn in Japan. The site now holds 2,700 photos, "including images of prints from earlier trips to Micronesia, China, Romania and Indonesia. The photos are all captioned and aim to be documentary more than artistic."

The journey has had some surprises, some pleasant, some simply surprising.

"One weekend we stopped in at Queen Emma’s Summer Palace," said Bradshaw. "Docent Susan Berg got interested in our project and introduced us to architect Bob Liljestrand, whose parents’ house had just recently been added to the National Register, one of Vladimir Ossipoff’s residential designs. It’s not often we get a chance to step inside private homes. Bob not only gave us a tour of the house, he also supplied a lot of high-quality photos."

And …

"One of the biggest disappointments was Pu’u’opae Bridge on Kauai. We drove all over looking for it and couldn’t believe what a rusty little one-lane wreck like that was doing on the National Register. The journey was more rewarding than the destination."