Boston 400 atlas
Historical event · June 15, 1780

Massachusetts Constitution Ratified (1780)

Drafted chiefly by John Adams and ratified June 15, 1780 — the oldest written constitution still in continuous effect anywhere in the world, and the model for the U.S. Constitution. Its "free and equal" clause ended slavery in Massachusetts by court ruling within three years.

Why it matters

Boston’s most consequential export: the constitutional architecture the nation copied.

Open the full civic recordCurrent pulse, routes, recommendations, and memory
Living object

Now, then, future

Every object is temporal: what it feels like now, what it used to mean, and what it can become next.

Current modegolden hour
Historical echoJohn Winthrop
Connected eventBoston 400 — The Quadricentennial (2030)
Pulse

How it feels right now

Current energybusy but readable
Best nowone good detour
Best timegolden hour
serendipitous
Rain scoreexcellent

Indoor escapes within a few blocks.

Laptop friendlinesslow

Coffee, libraries, bookstores, and campus edges.

Student presencehigh

How strongly the nearby graph reads as campus life.

Tourist pressurelow

Fame, landmark pull, and visitor-facing assets.

Historic densitystrong

Older records and historical edges around this object.

Serendipityhigh

Different kinds of things hiding within a short walk.

Turn this into a walk

Routes with a point of view

What should I see next?

Chosen moves from here

The editor's hand

Human recommendations

Civic memory

What this meant before

Date
June 15, 1780
Graph connections
2

In the graph 2 relationships — first-class data, not links

Explore Massachusetts Constitution Ratified (1780) in the interactive Graph Explorer — click to expand every connection →
Located in
Boston

Nearby what sits within a few minutes’ walk

An unexpected connection

Massachusetts Constitution Ratified (1780) is linked, through the graph, to Boston city, 5 min walk away. The kind of thread you only find by following the connections.

Keep exploring graph-powered — every path below is a real relationship, not a guess

One record, 1 framing cross-property publishing — never duplicated

Boston400.com · you are here

How we know graph confidence — we explain our certainty, not just assert it

Source qualityBest source is primary / institutional
Independent corroboration2 sources
Human-reviewedEditorially verified
Institutional backingCites a primary or institutional source
Record completeness80% of canonical fields present
Sources, by tier
Commonwealth of Massachusetts Primary / institutional
Mass. Historical Society Primary / institutional
Graph scores — our north star is relationship density, not page count
Relationship density25
2 connections
Record coverage66
metadata completeness
Graph authority27
centrality + reach + trust
Schema.org JSON-LD — what answer engines read
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