ADAMS — The town has received 13 responses to a request to design and supervise building a estimated $5 million, 11,000-square-foot outdoor skiing and education center at the Greylock Glen.

It's a crucial next step in a decades-long effort to jump-start a $53 million cultural and eco-tourism education and entertainment center on the 1,064-acre public parcel abutting the Appalachian Trail and the state's highest peak — and largest public park.

Eleven of the 13 architectural and design firms that responded to the request for proposals are from Massachusetts, with one each from Vermont and Connecticut.

"Thirteen firms is a nice response," said Jean Rice, community development specialist for the town.

The town asked for expertise in "design of green building technologies." The request said a successful bidder would do schematic design, construction designs and would supervise construction.

The disclosure comes six weeks after North Adams artist, architect and "green industry" entrepreneur Ralph Brill submitted a 140-acre campground proposal for "Hobbit-style" sleeping huts and rustic cabins and said he wanted to combine it with hostel-style lodging and virtual-reality training facility in the vacant Adams Memorial Middle School. Adams officials are now mulling his proposal.

Meanwhile, the Massachusetts Audubon Society confirmed it is watching the project with interest in possibly stepping forward to manage programs at the education center if it is built.

"We want very much to be a player when it comes to the Environmental Education/Nordic Ski Center," said Gail Yeo, vice president of wildlife sanctuaries and programs, in an email.

Audubon, the Massachusetts College of Liberal Arts, the Massachusetts Museum of Contemporary Art and the Appalachian Mountain Club all helped the town over the last several years to develop a comprehensive recreation-tourism-education plan for the Glen.

The 14-page request issued Dec. 21 by the town does not provide any estimate of the likely total cost of the education center, but it speaks about an intention that any respondent plan to help the town raise funds for costs in excess of the $5 million — before any detailed architectural drawings are created. It says the town will work "to secure construction funding for the proposed facility."

With 13 proposals in hand, the next step is for the town's Designer Selection Committee to sift through them.

The campground and education center comprise the first two pieces of the Glen project; the third would be an amphitheater and, ultimately, a 170-room lodge-style hotel. Only the education center is slated to be built in whole or part with public funds, but state money has already extended water, sewer and utility infrastructure to the sites, and put permits in place.

The request sent out in December described a "green" building including exhibit space, a media room, four classrooms, and an indoor-outdoor cafeteria. It's not clear how much of the design and construction would be covered by that figure.

The multi-use building would include space for a private-venture Nordic skiing operation, plus spaces for exhibits and a potential MCLA "field station" for its environmental studies program. There would be parking for 100 cars.

In keeping with its intention to be a key partner with Glen developers and operators, the town will "develop the final program scope and budget for the outdoor-center project in conjunction with the selected design consultant team using the design concept and other supporting materials created during schematic design phase and beyond," according to the request. It says utilities and all state and local permits are in place.

Once anticipated funding is in place, the request says, the town would authorize its consultants to prepare full construction plans, specifications and public-bidding documents.