Exploring 1938 San Francisco through aerial photography in Google Earth

Editors Note: Today’s guest author is David Rumsey, President of Cartography Associates and founder of the David Rumsey Map Collection, an online archive of historical maps and cartographic materials. Additional pieces from this collection can be viewed in Google Earth by browsing the Rumsey Historical Maps layer.

In August of 1938, a pioneer of aerial photography, Harrison Ryker, worked with pilots out of Oakland Airport to create a series of high resolution images of San Francisco. Each pilot flew from north to south, completing about 12 passes to create a group of vertical black-and-white photographs, overlapping each other by approximately 30 to 50 percent. The result was 164 large prints covering the entire city at about 1 meter resolution. Residents of San Francisco can enjoy these magnificent photographs by visiting the San Francisco Public Library. But if you don’t happen to be visiting the Bay Area anytime soon, you can also enjoy the entire collection online, courtesy of the David Rumsey Map Collection.

While cataloging these historic images, our team geo-referenced each photo to create a mosaic of all the images, corrected for terrain variation, lens distortion, and variance of angle. This was a challenging task because we did not have any records of the project’s camera calibration report, lens used, or any other specifics on how the original photos were produced. Rather, we had to rely on placing ground control points in the correct places to get the desired accuracy. Glenn Bachmann of the Rumsey Map Collection led this project, the results of which allow the 1938 imagery to be overlaid on current satellite views of the city in Google Earth when you turn on historical imagery for San Francisco. You can also view these historic photos in geographic context online in the Rumsey Historical Maps online gallery using the Google Earth plug-in. 

Composite of 1938 aerial photos of San Francisco

The individual aerial photos that make up the mosaic above of the entire city of San Francisco are each 50 cm high and 60 cm wide, with an effective scale of 1:2,000. The prints are in very good condition with high contrast and sharp detail, as you can see in the example below of the area around the Ferry Building at the foot of Market Street.

Aerial Photograph 18, area around the Ferry Building in San Francisco, 1938

It is endlessly fascinating to compare the city in 1938 to the current landscape. The area around the old Mission Bay has undergone a huge transformation: you can see the old Southern Pacific Railroad round house, which is now transforming into the University of California’s Mission Bay Campus.

Detail of Aerial Photograph 14, Mission Bay Railroad Yards, Southern Pacific Round House, San Francisco, 1938

Another part of the city that has experienced tremendous growth are the sand dunes of the Outer Sunset district, now filled in with the Doelger housing developments of the 1940’s.

Aerial Photograph 148, Sand dunes in the outer Sunset District, San Francisco, 1938

Some of the images show parts of the cities that are no longer part of the modern landscape. Below you can see the cemeteries around Lone Mountain that were moved to Colma in the 1940’s.

Aerial Photograph 85, Calvary and Laurel Hill Cemeteries, San Francisco, 1938

Learning more about the creator of this historical archive proved to be nearly as much of a challenge as geo-referencing and cataloging his work. After much sleuthing, Dan Holmes of the Rumsey Map Collection was able to uncover more detail about Harrison Ryker’s life and work online. You can read more about Mr. Ryker in our blog post about the aerial photographs on the David Rumsey Map Collection website.

We are grateful to the San Francisco Public Library and Susan Goldstein of the library’s San Francisco History Center for making these amazing photographs available to the public, and for saving and preserving them for the past 74 years! 

This is an exciting time for historical aerial photography. New technology creates a platform for these images to be scanned, georectified, mosaicked and enjoyed by people all over the globe. Google Earth and Google Maps give new life to these images, pulling them out of the archives and encouraging comparison to present-day imagery. These photographs combine the best aspects of photographic veracity and immediacy with the scale, artistry, and cartographic tools of mapping. It is like combining a photograph and a map of the same place, together. We hope that more of these aerial photographs will be scanned and geo-referenced, covering all parts of our globe, helping us to see in detail how the world looked from above, long ago. 


Posted by David Rumsey, founder of the David Rumsey Map Collection

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The journey to bring Iraq’s National Museum to Street View

Over the years, our Street View technology has been used to showcase images from a variety of amazing locations around the world. Without the stress of travelling, we’ve all been able to tour places like Stonehenge, Palace and Park of Versailles, and even Half Moon Island (with the penguins!) in Antarctica. Starting today, you can view Iraq’s National Museum in Baghdad on Google Maps, in our Street View Gallery and on the museum’s own website.

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Street View of Iraq National Museum

The project began in October 2009, when the Street View team had the opportunity to visit Baghdad to collaborate with the museum. By this time, the Iraqi National Museum had recovered a slew of articles that were infamously looted during the US invasion of Iraq in 2003. The collection hosts a staggering wealth of artifacts dating back to some of the earliest human settlements, which developed around present day Iraq. The history of this area is often underrepresented, or otherwise inaccessible, in large part due to the political strife that has plagued Iraq. For this reason, we considered it an important opportunity to showcase Iraq’s National Museum in our Street View Gallery.

Dan Ratner, Matt Williams and myself in front of the museum.

This was our first attempt to capture an indoor collection at a museum, and we met a host of logistical and technical challenges. While we already had Street View cars visiting cultural landmarks, taking panoramic photos indoors was an untested idea. We had recently completed a prototype of our indoor trolley - which was later used and refined for the Google Art Project, but we were unsure that it would perform how we had envisioned on-site.



For security reasons, we could only spend 4 consecutive hours at the museum per visit. This meant our time there was frantic. We spent most of our first trip assembling and testing the Street View Trolley, installing car batteries that had been hastily acquired in Baghdad, testing GPS antennas, and making numerous satellite phone calls to our Mountain View headquarters to debug issues. While some of us worked on setting up the Trolley, others were photographing everything possible in the museum, trying not to get distracted by artifacts dating back over 6000 years.

Using the Street View indoor trolley to collect imagery

With the Street View Trolley working, we spent our second visit collecting images of the main exhibit halls. We also used high-resolution imaging equipment that enabled a close-up 360-degree view of individual artifacts, a selection of which are viewable on the Antiquities page of the Museum website. We imaged a Mother Goddess figurine that predates recorded history, cuneiform tablets that exemplify one of the earliest forms of writing, and several exquisite examples of early Middle Eastern pottery.

Goddess Figurine

This piece, a clay figurine of a female from the Samarra period, was found at Tell Songor A. The 10.2 cm statue dates back to 5000 BC.

Although we only spent a week in Baghdad, we returned with tens of thousands of still photos. We spent months processing the images - which includes stitching them into the immersive panoramic images you’re accustomed to when using Street View in Google Maps - and working closely with the National Museum to incorporate the imagery into their new website. At long last, we’re thrilled to jointly release the imagery, enabling users anywhere in the world to virtually visit the museum’s exhibit halls and learn more about Iraqi culture through this collection.



For those whose interest is piqued by the collection and are considering visiting the museum in person, we hope these online images tides you over until the official museum reopening planned for later this year. You can experience the the Iraqi National Museum for yourself through our Street View feature in Google Maps, via our Street View Gallery, or take a virtual tour on the museum website.



Posted by Alex Starns, Technical Program Manager

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Let Historypin be your guide

Editor’s Note: Today's guest author is Nick Stanhope, co-founder and executive director of an awesome and inspiring website out of the UK called Historypin. We collaborated with the site for its launch as a beta last year, and Nick is writing a guest post to announce today's official launch of Historypin with a new mobile app and expanded global availability. His team’s labor of love illustrates the amazing ways individuals and organizations can use Google Maps and Street View to share new (or in this case, old) views of the world around us.

A few years ago, just before she passed away, my Gran and I spent a lot of time together looking through some of her old photos and family videos, sharing stories and learning a bit more about each other’s lives. This picture of my Gran and Great Auntie Jenny, working as land girls in the summer of 1943, was one of my favourites.

Everyone can identify with this sense of wistfulness and nostalgia that memories often evoke. Sometimes it’s triggered by talking to a grandparent about what they did at your age, by learning more about the guy in the photo who looks like a Victorian version of your Uncle Phil, or by chatting with an older neighbour about how different Main Street looked fifty years ago.

This is what Historypin is all about: conversations between different generations and neighbours, time spent around sights and sounds of the past, stories remembered and shared and comparisons made between then and now. And today, we’re thrilled to announce its graduation from last year’s beta phase with worldwide availability, the addition of a new mobile app, and a bunch of other exciting new developments.

Historypin is a website and smartphone app that uses Google technology in new and creative ways. You can explore old photos, videos and audio clips that have been “pinned” onto Google Maps (which you can search not only by location but also by date), compare these glimpses of the past with how they look in today by seeing them overlaid onto Street View, immerse yourself in local history using the Android app, journey through Tours and Collections of featured content and, best of all, “pin” your own history as photos, videos, audio clips and stories to the site.

And by continuing to work closely with Google, we’re excited about the improvements to come as well. Later this year, we’ll launch additional new features like embed tools that enable you to put Historypin on your own site, Historypin channels that will allow you to create your own distinct experiences, and pinning games that invite the community to pin content that we and our partners know little about.

But, really, it’s not about the tech. It’s about those conversations - little ones, across families and streets, and big ones, involving millions of citizen historians. Through all of these conversations, we can create a place to explore history in amazing ways and help families and neighbourhoods come together around what we all share: history.



Posted by Nick Stanhope, Co-Founder & Executive Director, Historypin

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