For unique things to do in Boston, walk across the glass bridge inside the Mapparium, a stained-glass globe about 30 feet high at the Mary Baker Eddy Library; pay for a day in the Boston Athenaeum, a private library on Beacon Street; and hunt down two odd downtown markers, the Boston Stone on Marshall Street and the Great Molasses Flood plaque in the North End. Most of these take under an hour and cost little or nothing.
None of them needs a full day, so they slot around the big sights. Here is what each one is, what it costs and the practical catch.
Offbeat Boston at a glance
| Stop | Neighborhood | Cost | Catch |
|---|---|---|---|
| Mapparium | Back Bay | Ticketed | Check the library site for times |
| Boston Athenaeum | Beacon Hill | $11 first floor; $40 day pass | Closed Sundays |
| Boston Stone | Downtown | Free | Easy to walk past |
| Molasses Flood plaque | North End | Free | In a ballpark, near home plate |
| Brattle Book Shop lot | Downtown Crossing | Free to browse | Closed Sundays |
| Old North bell chamber | North End | $15 adult | Two steep stairways |
| Gardner Museum | Fenway | Free if your name is Isabella | Timed entry, closed Tuesdays |
| Piers Park | East Boston | Free | Across the harbor |
The Mapparium: walk through a glass globe
The Mapparium is a walk-through globe made of stained glass, completed in 1935 for the Christian Science Publishing Society, at the Mary Baker Eddy Library, 210 Massachusetts Avenue. A bridge runs through the center of the sphere, which the library gives as 9 meters (about 30 feet) tall, so you stand in the middle of the world as it was mapped in the 1930s, with borders that no longer exist. The glass does not absorb sound, which produces its best-known trick: a voice at one end of the bridge carries clearly to the other. Visits are part of the library's How Do You See the World? experience; the atrium is open Monday to Saturday 10 a.m. to 5 p.m. and Sunday 11 a.m. to 5 p.m., and it closes on Massachusetts legal holidays.
Boston Athenaeum: a library you can pay to enter
The Boston Athenaeum at 10½ Beacon Street is a members' library, but non-members can buy in. First-floor admission is $11 for visitors 14 and up, and a $40 day membership opens all 12 floors, reading rooms and city views included. One-hour docent-led Art and Architecture tours include first-floor admission and often sell out. It is open Monday to Thursday 9 a.m. to 8 p.m. and Friday and Saturday 9 a.m. to 5 p.m.; Park Street station is the closest T stop.
The Boston Stone: an odd marker with a doubtful story
Set into the base of a brick building at 9 Marshall Street, beside the Blackstone Block, is a round granite stone about two feet across, labeled Boston Stone 1737. The usual account is that the merchant Thomas Childs brought it from England around 1700 to grind pigment in his paint mill, and that it was set into the wall when the present building went up in 1836. The claim that it marked the center of Boston for measuring distances does not hold up, since the region's milestones were measured from the Old State House, and the inscription may have been a shopkeeper's bid for attention. It is two minutes from Union Oyster House.
The Great Molasses Flood plaque
On January 15, 1919, a molasses tank at 529 Commercial Street in the North End burst, sending a wave of molasses through the neighborhood and killing 21 people. A small plaque marks the site in Langone Park on Commercial Street. Since the park's 2021 renovation it has stood just outside the baseball field's home plate, so look there rather than along the old perimeter wall.
Brattle Book Shop's outdoor lot
Brattle Book Shop at 9 West Street dates to 1825 and fills three floors, with rare and antiquarian books on the third. The draw for a quick visit is the outdoor sale lot beside the building, stacked with discounted shelves. It is open Monday to Saturday 9 a.m. to 5:30 p.m.
Old North Church's bell chamber
At Old North Church in the North End, the guided bell chamber tour takes you about a third of the way up the tower, to the bells a teenage Paul Revere rang. It lasts 25 minutes, climbs two sets of steep stairs and costs $15 for adults with the self-guided Discovery Pass included.
Free entry at the Gardner if your name is Isabella
The Isabella Stewart Gardner Museum in the Fenway admits anyone named Isabella free with valid ID, a rule that honors its founder. Everyone else can come free on Thursday evenings from 5 to 9 p.m. Entry is by timed ticket and the museum is closed on Tuesdays.
Piers Park: the skyline from East Boston
Piers Park, at 95 Marginal Street in East Boston, is a harborfront park with a long pier that looks straight back at the downtown skyline, a view most visitors only see from a plane. Pair it with a meal in East Boston, such as Santarpio's Pizza.
For more ideas off the main route, see our guides to unusual things to do in Boston, nerdy things to do in Boston and cheap things to do in Boston.
Sources: Mary Baker Eddy Library, Boston Athenaeum, Brattle Book Shop, Old North Church, Isabella Stewart Gardner Museum; Boston Stone and Molasses Flood histories from published accounts. Checked September 30, 2026.