Openhistoricalmap page not loading?

JSR1781 · December 4, 2025, 11:28pm

So right now, OpenHistoricalMap is displaying a 403 forbidden error, can anyone explain why? OpenHistoricalMap has been giving errors this week.

Minh_Nguyen · December 4, 2025, 11:47pm

It’s working for me, but do you get any details along with the 403 error? I wonder if you’re being rate limited. We had to put in a rate limit earlier this week in response to extremely aggressive scraping by botnets (probably for LLM training purposes). It might need some adjustments.

ECRock · December 5, 2025, 12:15am

I can barely make a few edits before seeing a disconnect message with the API. Then if I refresh I get this message.

Minh_Nguyen · December 5, 2025, 4:12am

Yes, that’s the rate limiting. Sorry it’s impacting you. It seems like it’s easier to hit the rate limit in iD than in other editors for some reason. We’re looking into a less invasive approach to defending against the bot attacks so we don’t have extended downtime.

github.com/OpenHistoricalMap/issues

Bot traffic spike from distributed ips threatens OHM

opened 12:39AM - 02 Dec 25 UTC

Rub21

The current issue involves an unusually high volume of bot traffic generating ex…cessive requests against both the Staging and Production environments. This activity far exceeds normal levels and poses a risk to the site's stability. While we are already blocking certain IP addresses and providers through [https://github.com/OpenHistoricalMap/bot-ip-blocker](https://github.com/OpenHistoricalMap/bot-ip-blocker), only a portion of these requests is successfully stopped. The remaining traffic originates from a distributed network of IPs across multiple countries, making it difficult to control by source alone. *Example of incoming requests to openhistoricalmap.org during a 1-hour period:* <img width="834" height="517" alt="Image" src="https://github.com/user-attachments/assets/9e81e9d6-a951-481e-b618-6cd47dc37fed" /> To mitigate this, a rate limit has been configured in AWS to restrict the number of requests per minute. Any IP generating more than 100 requests within a single minute is automatically blocked. *Number of requests blocked after implementing rate limits:* <img width="1104" height="672" alt="Image" src="https://github.com/user-attachments/assets/8db6bf77-c6dd-4ed7-9910-44c03f6fc134" /> The related alert appearing in Slack is also linked to this bot activity, as PostgreSQL eventually exhausted all available client connections during peak traffic periods. <img width="986" height="358" alt="Image" src="https://github.com/user-attachments/assets/3e73a6a3-e32f-43d6-b5c0-e55ce6235d6f" /> Although rate limiting has reduced some of the impact, new patterns of bot traffic continue to appear. We need to strengthen these countermeasures to identify and block such requests more effectively.

Rub21 · December 5, 2025, 4:20am

Sorry for the inconvenience. We implemented rate limits in response to a surge of bot traffic targeting OHM. I’ve just raised the current rate limits, and we’re also rolling out additional measures to permanently eliminate the need for rate limiting while effectively blocking abusive bots.

Alphathon · December 5, 2025, 10:11am

For what it’s worth I’m also getting the 403 error. All it says is “403 Forbidden” – no other info is given. This is just trying to load the website, not iD or anything; I can use the vector tiles and download data in JOSM just fine, at least in the limited tests I’ve done. If I go to https://embed.openhistoricalmap.org/ the page loads – there is no error, I can pan around and the widgets are shown on the side – but no map data is displayed, it’s just white.

Might it be some regional server issue or something, hence Minh_Nguyen not seeing it. (I’m in the UK if that’s relevant.)

Minh_Nguyen · December 5, 2025, 2:49pm

Huh, so you’re only seeing a bare HTTP error page rather than the “Access temporarily limited” message?

The embed site is served from separate infrastructure (GitHub Pages), but the tiles come from our own infrastructure, so the 403 error would result in blank tiles but the page would still load.

Alphathon · December 5, 2025, 3:23pm

Yeah, that’s right.

That sounds right. The console says it 403s on https://www.openhistoricalmap.org/map-styles/main/main.json and “has been blocked by CORS policy: No ‘Access-Control-Allow-Origin’ header is present on the requested resource”.

Edit:

It seems to be loading OK on other devices on my home network so there’s something else going on.

ECRock · December 5, 2025, 11:10pm

@Minh_Nguyen @Rub21 Understood! Thanks for confirming and I’ll look forward to the permanent fix.

Minh_Nguyen · December 6, 2025, 12:18am

We’ve disabled the rate limit while we investigate a less invasive approach to protecting the site. Apologies for the disruption!

JSR1781 · December 6, 2025, 2:23am

So i found a solution.

I use Microsoft Edge as my main search engine but i loaded openhistoricalmap.org into Google Chrome and it works perfectly.

Comparison:

Google Chrome

JSR1781 · December 6, 2025, 2:24am

And Microsoft Edge.

Minh_Nguyen · December 6, 2025, 3:03am

Which versions of Edge and Chrome are you running? I wonder if you (and everyone else who got the 403 error) got snagged by the other approach we’ve taken, blocking certain user agent strings.

Alphathon · December 6, 2025, 11:21am

In my case that seems extremely likely (it’s not worth going in to) and I did wonder if something like that was going on.

Edit: I can confirm that the user agent was definitely my issue.

JSR1781 · December 6, 2025, 3:18pm

!!

Microsoft Edge openhistoricalmap.org is now loading for me.

Minh_Nguyen i don’t know about the versions of Microsoft Edge and Google Chrome im using, sorry for the inconvenience.