Fire insurance maps are an invaluable tool for history research: they give a detailed snapshot of a city’s built environment at a given point in time. And they were made for just about every city, town and village. The Library of Congress has 50,000 fire insurance maps (700,000 individual sheets) in its collection, most of which were produced by the Sanborn Map Company. The Library has just released a resource guide to help researchers navigate its collection, and explain which maps are available (copyright is an issue with more recent maps). Announcement here.
This interactive map compares U.S. COVID vaccination rates with active cases at the county level. Created by McKinsey and Company’s COVID Response Center, it’s a bivariate choropleth map that shows two variables at once. (If this confuses you, the legend helps.) It’s a good way to see where low vaccination rates correlate with lots of COVID cases (red on this map), or high vaccination rates with few cases (teal); the map lets you explore other variables as well. [Maps Mania]
The Verge maps the gaps in U.S. broadband coverage. “This map shows where the broadband problem is worst—the areas where the difficulty of reliably connecting to the internet has gotten bad enough to become a drag on everyday life. Specifically, the colored-in areas show US counties where less than 15 percent of households are using the internet at broadband speed, defined as 25Mbps download speed. (That’s already a pretty low threshold for calling something ‘high-speed internet,’ but since it’s the Federal Communications Commission’s standard, we’ll stick with it.)” They’re using anonymized Microsoft cloud data rather than the FCC’s numbers (which don’t have a good track record reflecting real-world speeds).
The French state railway company SNCF has a lot of nice maps of their rail network, some of which I’ve posted here before; of particular interest, though, is the Atlas du réseau ferré en France, which gathers them into an 86-page booklet, and includes a lot of diagrams showing, for example, passenger and freight volumes. It’s available here as a flipbook and can be downloaded as a PDF if you give them your email; I’d be over the moon if it existed as a hard copy.
For her upcoming fantasy novel The Freedom Race (Tor, July 2021), Lucinda Roy decided to do what a lot of fantasy authors do: draw a map. But she did it in a way that most fantasy authors don’t: “I needed a persona map—a map that could feasibly have been drawn by Ji-ji, the main character in the book. Her map doesn’t simply introduce the world to readers, it actually appears inside the narrative and helps catalyze the action.” Then she decided that she needed two maps, both intrinsic parts of the story, both revealing a great deal about their respective mapmakers. Very much relevant to my interests: I wrote, after all, a piece about fantasy maps in fantasy worlds (and got some flack for it). Though it’s the first time I’ve heard the term persona map. A new term of art?
In 2021, Nathan Thomas and Lola Fatoyinbo of NASA’s Goddard Space Flight Center, along with colleagues from three countries, took another step by mating ICESat-2 measurements with images from Copernicus Sentinel-2 to derive bathymetry at better resolution. The team mapped the shallows down a depth of 26 meters (85 feet) around Biscayne Bay in Florida, the Gulf of Chania in Crete, and the island of Bermuda.
Thomas and colleagues compared their satellite-derived bathymetry with maps made from traditional topographic surveys, multibeam sonar, and nautical soundings. Their new maps had a resolution of 10 meters, improving upon the current 115-meter resolution dataset for Crete and the 30- to 90-meter datasets for Florida and Bermuda. The existing data for Florida and Bermuda are composites of lots of sources spanning 63 years, while the ICESat-2/Sentinel-2 maps offer a contemporary assessment of underwater structure.
It’s a shame that Sarah Battersby’s essay in The International Journal of Cartography, “The Unicorn of Map Projections,” is behind a paywall: it looks at the recent rash of map projections that purport to solve “all our mapping problems.” There have been more than a few that have claimed the title of “most accurate map”; Battersby refers to these projections as a class as unicorns. The most recent example of this I dismissed as the cartographic equivalent of a spherical cow; five years ago there was also Narukawa’s AuthaGraph map; and of course there was the Peters map.
Justin O’Beirne reports that the next expansion of Apple’s new maps will cover Spain and Portugal, making them the first non-English-speaking countries to receive the upgrade. The new maps are currently in testing; a small number of users may already be able to see them.
About 500 of you subscribe to The Map Room via its email digest. That feature is powered by FeedBurner. Last week FeedBurner announced that it’s being moved to new infrastructure. Several features will as a result be discontinued—including email subscriptions. I’ve been investigating possible alternatives. The one that looms largest is Mailchimp; its free plan maxes out at 2,000 subscribers, which is four times what we need right now, so there’d be room to grow—but that limit is a hard limit (Mailchimp’s paid plans are way too expensive given this little website’s income). In any event I’ve got some time—until July, I think—to come up with a solution. Will keep you posted.
Canadian Geographic on a project to map Nitassinan, the ancestral homeland of the Innu in Labrador and eastern Quebec. “It started with a few illustrated maps for two small schools. Two printed editions, one giant floor map in-the-making, and layers upon layers of watercolour later, the Nitassinan map project is grabbing attention across Canada.”
Nothing wrong with it as a fun exercise, but can it actually be used? As someone who back in the day biked quite a lot of the Ottawa and Gatineau bike trail network, I can’t use this map. I don’t recognize the path network. Part of it is because many of those paths have names that he doesn’t use; part of it is the conceit of creating “stations”; part of it is that a surface path network that can be entered or exited at any point is not well served by a network diagram. It makes sense to abstract a subway network from the street level, because you’re basically travelling from station to station. You’re not doing that on a bike; you’re in the neighbourhood.
The Centers for Disease Control and Prevention released data and maps showing the estimated rate of COVID-19 vaccine hesitancy in the U.S. on a county-by-county basis. The data is based on a question in the Census Bureau’s Household Pulse Survey that asked respondents whether they’d get a vaccine for COVID-19 once it was available to them. Methodology and datasets here. [Boston.com]
Metropolitan France—mainland France without Corsica and its overseas territories—is often referred to colloquially as l’Hexagone. Jug Cerovic, whose work we are familiar with here, has taken that metaphor and run with it with this network diagram of France’s main passenger train lines: the grid is hexagonal, and it works. Lines are colour-coded: TGV lines are blue if they start in Paris and red if they route around it or connect regions directly (a relatively new development; intercity lines are blue-grey, regional lines are orange, and night trains are grey. International routes are also included. It’s actually quite easy to see what cities and towns get what kind of train service, and what services exist between two points—exactly what a network map should do.
The French state railway company SNCF has a lot of nice 
