Privacy

What Henge Days records while you use it, and why.

What is recorded

The addresses and place names you search for, where they resolved to, and whether a building outline was found. This is how search problems get found and fixed.
For a plan along a street: the street's name, the distance between the two ends, the day, and whether the street was found. The two addresses themselves are kept only as searches, as above.
Which features you use: outline loads, calendars computed, calendar files downloaded, walls selected, tabs opened.
When you press Share, the link that was copied. For the first page you open on each visit, the page's address and the name of the website you came from, such as google.com, without the rest of that site's address.
When a chat or social app such as Messages, Slack or WhatsApp fetches a page of Henge Days to show a preview of a link, the name of the app and the page's address. Nothing about the person who pasted the link is recorded.
When an AI assistant such as ChatGPT, Claude or Perplexity, or a search engine's crawler, fetches a page, the agent's name, the page's address and whether it took the page's Markdown form. Nothing about the person who asked the assistant is recorded.
For each building page viewed, the building's name, the center of its outline, its next head-on day and the dates of each wall's head-on windows in the next 12 months are kept for 60 days, so that a shared link to the page, or to one wall and date on it, shows them in its preview. For each street planned, the street's name, the coordinates of its two ends, the day, the count of walls that get the sun and the first three stops are kept the same way. Nothing about who viewed the page is kept with them.
A random id stored in your browser, so that one visit can be told apart from another. It is not linked to your name or email unless you give them in feedback.
Your browser type, the country your connection comes from, and the version of the site you were using.
Google Analytics, a service from Google, records which pages are viewed and standard visit information such as browser and country, under Google's terms. It receives the web address of each page, and the address of a building page contains the place you searched for. Henge Days does not send it your email address or anything else you type.
Anything you type into the feedback form, with the page and building you were looking at. Your email address is kept if you enter it, or if you are signed in. Each message is also emailed to the site's owner, and the owner is emailed when an account is created.

If you sign in

Your email address is stored with your account. Sign-in emails are sent by Supabase, the service that holds the account database.
The buildings and henge days you save are stored under your account, with the building outline, the wall they refer to, any note you add, and whether you marked a day as shot or missed.
If you open the calendar feed in the planner, a secret link is made for your account. Anyone who has the link can read your saved days. Each time a calendar app reads it, the time of the read is recorded. Get a new link from the planner to stop the old one.
Usage records and feedback made while signed in are linked to your account instead of only to the browser id. The owner can see which account a piece of feedback came from.
A reply from the owner to your feedback is stored with it and shown in the feedback dialog. The time you first open a reply is recorded, so the Feedback button can stop counting it as unread.
Signing out ends the link. To delete your account and everything under it, use the Feedback button and ask.

What is not recorded

Your IP address is not stored.
Your precise location is not requested. The map's locate button, if you use it, stays in your browser.
To show a cloud forecast, the coordinates of a wall and the time of its head-on minute are sent to Open-Meteo, the weather service. No account or browser id goes with them.
The address you enter in the newsletter form goes to Substack, the service that sends the Henge Days newsletter, under Substack's terms. Henge Days does not record it, and your account on Henge Days is not subscribed to the newsletter. Henge Days records that a form was sent, and whether you opened or closed the newsletter banner at the top of an article. Your browser keeps when you closed the banner, or that you subscribed, so the banner stays hidden.
No advertising, and nothing is sold or shared. Google Analytics, listed above, is the only service from another company that records visits.

How long it is kept

Usage records are kept for up to 12 months. Feedback is kept until it has been dealt with and for 12 months after that.

Questions

Use the Feedback button on any page.

Terms and accuracy

How the dates and times on Henge Days are made, what they leave out, and the terms for using them.

This page is written in plain words. It is not legal advice.

What the dates are

Every date and time on Henge Days is computed. Nobody has stood at a given building on a given date to check it.

The sun's position comes from the NOAA solar position algorithm, accurate to about a hundredth of a degree. Refraction, the bending of light near the horizon, is included. This is the most reliable part of the result.
Building outlines come from OpenStreetMap, a map drawn by volunteers. An outline can be missing, simplified, a few meters out of place, or rotated by a degree or two.
A one degree error in the direction a wall faces moves the head-on moment by about four minutes. It can move a henge window by several days.
Addresses are looked up with public geocoders: Nominatim, the US Census Bureau geocoder and Photon. A search can land on the wrong building or on a range of addresses. Henge Days shows a warning when a match is known to be approximate or shared.

What is not included

Terrain and the horizon. Sunrise and sunset here mean the sun crossing a flat horizon. Hills, other buildings and trees can block a low sun for minutes or for the whole event.
Weather. The cloud figures shown for the next ten days are forecasts from Open-Meteo for that minute. A forecast can be wrong on the day. Haze, fog and smoke are not shown.
Access to the place you would stand: closures, traffic, construction, private property and local rules.
Clock times use the time zone of the building's location from the IANA time zone database (the standard list of world time zones), with daylight saving time applied. Check the time zone if the building is near a time zone border.

No warranty

Henge Days and everything it shows are provided as is. There is no warranty of any kind, express or implied, that the information is accurate, complete, or fit for any purpose.

Your responsibility

Check a location yourself before you rely on a date, travel to it, or plan a shoot around it. You are responsible for your own safety, for having the right to be where you stand, and for your own costs. Do not stand in a road to take a picture.

Liability

To the extent the law allows, the operator of Henge Days is not liable for any loss, injury, damage, expense or disappointment that arises from using the information on this site. This applies whether the information turns out to be accurate or not. It includes travel and booking costs and a missed sunrise or sunset.

Changes to the service

Henge Days can change, give different results, or stop at any time, without notice. Results for a building can change when its outline is edited in OpenStreetMap.

Map and address data

Building footprints are © OpenStreetMap contributors and available under the Open Database License (ODbL). Geocoding is by Nominatim, Photon and the US Census Bureau, and the basemap is by OpenFreeMap. Each of these services has its own terms.

Acceptable use

The Henge Days API is private and serves only the pages of this site. Do not scrape the site, call the API from scripts or other programs, or download results in bulk.

Questions

Use the Feedback button on any page.

Admin Dashboard

What needs a look since your last visit, then the site's health, where visitors come from, what they do, the feedback and accounts, and what Cloudflare and Supabase are costing.

Planner

Your buildings, with the map, the walls and the days you plan to be there.

Articles · October 17, 2026

Family Weekend, in the right light: 26 East Coast colleges, October 16 to November 8, 2026

For families visiting a college this fall: the walls on each campus and in the town beside it that the sunrise or sunset lands on square during Family Weekend, when to be there between the events, and where to stand for the family picture. One article per school, 26 schools, three weekends.

For October 16 to November 8, 2026.

Twenty-six East Coast colleges hold Family Weekend between October 16 and November 8, 2026, in three clusters. For each one, Henge Days has computed the walls on the campus and in the town beside it that the rising or setting sun lands on square that weekend, from building outlines, and an article gives the buildings a visiting family walks past anyway, the weekend's schedule with the light written in beside it, and the spot and the quarter hour for the family picture. Post yours with #HengeDays.

The articles arrive school by school over the coming days; a card below opens when its article is up, and the rest say Coming. Every date and time comes from the Henge Days engine for the wall's own bearing, each entry carries the accuracy note, and no stand point is in a road.

Weekend 1October 16 to 181 school, 1 writtenSunset Saturday 6:27 PM Weekend 2October 22 to 2517 schools, 17 writtenSunset Saturday 5:48 to 6:52 PM Weekend 3October 30 to November 13 schoolsSunset Saturday 5:31 to 6:00 PM Weekend 4November 4 to 85 schoolsSunset Saturday 4:35 to 5:35 PM

Each dot is a campus, at its latitude and longitude, colored by weekend; a filled dot has its article. The coastline is not drawn.

October 16 to 18

George Mason UniversityFairfax, VA · October 16 to 18Sunrise 7:20 AM · Sunset 6:27 PMRead

October 22 to 25

October 30 to November 1

Middlebury CollegeMiddlebury, VT · October 30 to November 1Sunrise 7:27 AM · Sunset 5:44 PMComing
Bowdoin CollegeBrunswick, ME · October 30 to November 1Sunrise 7:14 AM · Sunset 5:31 PMComing
Swarthmore CollegeSwarthmore, PA · October 30 and 31Sunrise 7:29 AM · Sunset 6:00 PMComing

November 4 to 8

College of CharlestonCharleston, SC · November 4 to 8Sunrise 6:42 AM · Sunset 5:23 PMComing
University of GeorgiaAthens, GA · November 5 to 8Sunrise 6:58 AM · Sunset 5:35 PMComing
Amherst CollegeAmherst, MA · November 6 to 8Sunrise 6:30 AM · Sunset 4:35 PMComing
Princeton UniversityPrinceton, NJ · November 6 and 7Sunrise 6:35 AM · Sunset 4:48 PMfirst-year families
Rollins CollegeWinter Park, FL · November 6 to 8Sunrise 6:41 AM · Sunset 5:35 PMComing

Every school, with the sun times

School	City	Family Weekend	Sunrise Sat	Sunset Sat	Article
George Mason University	Fairfax, VA	October 16 to 18	7:20 AM	6:27 PM	Published
University of Virginia	Charlottesville, VA	October 23 to 25	7:31 AM	6:24 PM	Published
Christopher Newport University	Newport News, VA	October 23 to 25	7:22 AM	6:17 PM	Published
UNC Chapel Hill	Chapel Hill, NC	October 23 to 25	7:31 AM	6:29 PM	Published
Appalachian State University	Boone, NC	October 22 to 25	7:41 AM	6:39 PM	Published
Emory University	Atlanta, GA	October 22 to 25	7:49 AM	6:52 PM	Published
Harvard University	Cambridge, MA	October 22 to 25	7:08 AM	5:48 PM	Published
MIT	Cambridge, MA	October 23 and 24	7:07 AM	5:48 PM	Published
Northeastern University	Boston, MA	October 23 to 25	7:07 AM	5:48 PM	Published
UMass Lowell	Lowell, MA	October 23 to 25	7:09 AM	5:48 PM	Published
University of Rhode Island	Kingston, RI	October 23 to 25	7:08 AM	5:51 PM	Published
Trinity College	Hartford, CT	October 23 and 24	7:13 AM	5:55 PM	Published
Fairfield University	Fairfield, CT	October 23 to 25	7:14 AM	5:58 PM	Published
Columbia University	New York, NY	October 23 and 24	7:17 AM	6:02 PM	Published
NYU	New York, NY	October 22 to 25	7:17 AM	6:02 PM	Published
Fordham University	Bronx, NY	October 23 to 25	7:16 AM	6:01 PM	Published
University of Pennsylvania	Philadelphia, PA	October 23 to 25	7:20 AM	6:08 PM	Published
Haverford College	Haverford, PA	October 23 to 25	7:21 AM	6:08 PM	Published
Middlebury College	Middlebury, VT	October 30 to November 1	7:27 AM	5:44 PM	Coming
Bowdoin College	Brunswick, ME	October 30 to November 1	7:14 AM	5:31 PM	Coming
Swarthmore College	Swarthmore, PA	October 30 and 31	7:29 AM	6:00 PM	Coming
College of Charleston	Charleston, SC	November 4 to 8	6:42 AM	5:23 PM	Coming
University of Georgia	Athens, GA	November 5 to 8	6:58 AM	5:35 PM	Coming
Amherst College	Amherst, MA	November 6 to 8	6:30 AM	4:35 PM	Coming
Princeton University	Princeton, NJ	November 6 and 7	6:35 AM	4:48 PM	first-year families
Rollins College	Winter Park, FL	November 6 to 8	6:41 AM	5:35 PM	Coming

Sunrise and sunset are for the Saturday of each weekend, from the Henge Days engine, at the center of each campus, for a level horizon. The clocks go back on Sunday, November 1, so the November weekends are an hour earlier.

Schools that have not posted 2026 dates

Williams, Wellesley and Drexel held Family Weekend on October 24 to 26 last year, and Brandeis and Smith on October 31 to November 2. None had posted 2026 dates on October 17. They join the package when their dates appear.

How the list was made

The schools are the larger and best-known colleges from Maine to Florida whose Family Weekend was still ahead on October 17, 2026, found on the schools' own Family Weekend pages. For each campus, Henge Days computes every named building near a set of centers from OpenStreetMap outlines, keeps the walls where the sun lines up within 6 degrees of the horizon on the weekend's days, and traces the sun's path from each wall to drop the ones a neighboring building stands in front of. Hills and trees are not part of that check, and the times assume a level horizon; each article says so, and names any building that rises toward the sun from in front of a wall.

Any building has a page like the ones in these articles, your student's hall included. Whatever you shoot, post it with #HengeDays:

Look up a building Open your planner

Features

What Henge Days does, part by part, with a live example for each. Everything runs from a building's real outline and the sun's computed position.

Henge days for any building

Type an address or a landmark. Henge Days finds the building's outline in OpenStreetMap, gives every wall a compass bearing, and works out when the sun's bearing matches it. The Henge days tab lists every window for the next 12 or 24 months in date order: henge days with the sun on the horizon, golden light under 6°, low sun under 15°. Filters pick the tiers and sunrise or sunset. Each row has the best day, the time, a calendar event and a Save button.

Virginia Museum of Fine Arts, Richmond · Flatiron Building, New York

Today

The Today tab shows the chosen day for the selected wall: a timeline of when the sun strikes it and how squarely, the head-on minute, and the week ahead. The day can be any day you choose. A cloud forecast from Open-Meteo sits beside each day within 10 days.

The museum today

Along a street

Two ends of one street, the street's name or route number, and a day. Henge Days stitches the street's OpenStreetMap ways into one path, keeps the walls within 60 m that face the road, and lists the ones the sun reaches that day in the order you pass them. Each stop has the distance from the first end, the side of the road, the time the sun is square to the wall or at its best angle, the tier, and the wall. The map draws the street and marks each lit wall. A plan covers up to 5 km of one street.

US 17 through Tappahannock, December 12 · Main Street, Mathews, October 24 · Arthur Ashe Boulevard, Richmond, November 17

Planner

Sign in with an email link to save buildings and days. The planner keeps an agenda of your saved days in date order, with a countdown, the cloud forecast, and a note for each. The shot card for a day gives a stand point 1.5 wall lengths back from the wall, links to open it in Apple Maps or Google Maps, an arrive-by time, and a Shot or Missed mark afterwards. The agenda also lists days coming up at your saved buildings that you have not saved yet.

Open the planner

Calendar feed and calendar files

Any row downloads a calendar event with the stand point in its location. The planner also offers a private calendar feed: subscribe once in Apple Calendar, Google Calendar or Outlook and every saved day appears and stays current. The feed link can be rotated at any time.

Henge pages

A set of pages, one per building or street, with every head-on date and time for the year ahead written out on the page, computed when the site is built. They are for reading, for search engines and for AI assistants, and each has a Markdown form and a JSON file. The buildings and streets on the site's examples are there to start.

Henge pages

The Share button copies a link to the building, the selected wall and the map view. Pasted into a message or a post, the link shows the building's name and its next henge day, or the wall and date of the row you selected.

A link to one row at the museum

Open data and accuracy

Building outlines come from OpenStreetMap. Addresses are looked up with Nominatim, Photon and the US Census Bureau geocoder. Sun positions come from the NOAA solar position algorithm, computed in your browser for every day in the range. Cloud forecasts come from Open-Meteo. None of the dates are checked on the ground: hills, trees, other buildings and weather are not included, so treat each one as a plan to confirm before you travel. Terms and accuracy has the detail.

The day the sun hits that wall head-on.

Light you can put in the calendar

Find a wall's days

Drive a street for the light

Plan the shot

Flatiron Building

Live right now

Three streets, live

Church Lane, Tappahannock, VA

Main Street, Mathews, VA

North Arthur Ashe Boulevard, Richmond, VA

What is a henge day?

How it works

Privacy

What is recorded

If you sign in

What is not recorded

How long it is kept

Questions

Terms and accuracy

What the dates are

What is not included

No warranty

Your responsibility

Liability

Changes to the service

Map and address data

Acceptable use

Questions

Admin Dashboard

Planner

Release notes

Family Weekend, in the right light: 26 East Coast colleges, October 16 to November 8, 2026

October 16 to 18

October 22 to 25

October 30 to November 1

November 4 to 8

Every school, with the sun times

Schools that have not posted 2026 dates

How the list was made

Features

Henge days for any building

Today

Along a street

Planner

Calendar feed and calendar files

Henge pages

Share links

Open data and accuracy