On the Map: Where Were You When?

Illustration showing Earth in the Early Carboniferous period by Christopher Scotese
Earth in the Early Carboniferous period. Source: Christopher Scotese

By Allison Rivera

It is no secret that the Earth has drastically changed throughout history, though it can be hard to capture evidence of its evolution. Thanks to the innovative work of software engineer Ian Webster, you can explore Earth’s transformations in real time. Webster created an interactive “Ancient Earth” experience using the revolutionary work of palaeogeographer Christopher Scotese.

I always wanted to build a time machine. These maps allow me to travel back through time.

—Christopher Scotese

Scotese’s love and inspirations for paleogeography began during his childhood, when he would dream of traveling back in time. He recalls his ambitions from a young age: “I have had an interest in Earth History since childhood. During my summer vacations (age 8-10), I started a journal entitled A Review of Earth History by Eras and Periods. I always wanted to build a time machine. These maps allow me to ‘travel back through time.’”

It was from these ideas that his Atlas project was born. The Paleogeographic Atlas project began during his undergraduate career at the University of Illinois (Chicago). It was first published as what could be described as “flip books,” with some computer animations. It was not until his graduate career when the Atlas was updated to include principal scientific areas such as plate tectonics, paleomagnetism, and paleogeography. Despite other paleogeographic maps having been published at the time, these maps were noteworthy. The Atlas Project was the first to illustrate plate tectonics and paleogeographic evolution of the Earth. Scotese was also the first person to write software to animate the history of plate motions. However, he did face some challenges along the way. He noted that the greatest obstacle of the project was that “It takes a long time to accumulate the knowledge and experience to tell this story.” He is now writing a book titled The History of the Earth System, allowing him to compile the mass of information he has accrued over the years. Scotese also knew that updating the maps was no easy feat, and, with the help of many colleagues, has continued to integrate new and improved scientific ideas into the Atlas.

Scotese made sure to take many ideas into account from various scientists. Having worked with paleoclimatologist Judy Parish to incorporate paleoclimatic interpretations in the reconstructions of the Earth, he was able to develop a parametric climate model. Furthermore, Scotese used linear magnetic anomaly data and satellite imagery to create a model for Mesozoic and Cenozoic plate and ocean basin reconstruction. While his work paved the way for the current knowledge and understanding of time periods such as the Mesozoic and Cenozoic, those such as the Paleozoic remain unknown. Here, the map is based on information and results presented in a symposium on Paleozoic Paleogeography. The oldest map of the Atlas was the last to be assembled, but is based on a model Proterozoic plate tectonics, developed by Scotese and other geographers. From this, they were able to conclude that the Proterozoic was a time of Rodinia supercontinent assembly and breakup. Each map incorporates some form of scientific data and knowledge, making it as accurate as possible.

Despite the amount of collaboration, research, and time that went into this groundbreaking project, Scotese describes it as ongoing. The Atlas only describes the current knowledge and understanding of ancient Earth. As with any science project, new data and findings are always emerging, which leads to the need for constant updates and improvements to the Atlas. To keep up with new information, Scotese has a vision for a digital Atlas. Combining scientific data with technology such as GIS will allow for not only improved user friendliness but also easier compilation of data. Programs such as Paleo-GIS will be the foundation for the next version of the Atlas. In addition, Scotese is working with a group of scientists to add other Earth System information such paleoclimate, paleoenvironmental, biogeographic, and palaeoceanographic information.

Even though Webster’s project is based on the old version of the Atlas, it still has many features that make it easy to understand and educational. His work gives people living in today’s world a sense of connectedness to the ancient earth through time.

View Christopher Scoteses’s website Explore Ian Webster’s visualization of Dr. Scotese’s work


DOI: 10.14433/2017.0134


On the Map: Traveling by Trolley Back to the Dinosaurs

A cheerful yellow sign announces “Trolley Rides Today.” Credit: Paul Swansen, Flickr
A cheerful yellow sign announces “Trolley Rides Today.” Image by Paul Swansen, Flickr (CC BY-ND 2.0)


By Samantha Hinton

From the Fossil Trace Golf Course to the Denver Museum of Nature and Science, Denver is a modern city where the age of the dinosaurs is still present.  

One of the best ways to experience Denver’s dinosaurs is the Denver Trolley route (formerly called the Platte Valley Trolley route) to Lakewood Gulch, home to the site of the first Triceratops fossil ever found. 


Map showing the Denver Trolley route starting at Confluence Park in downtown Denver and hugging the Platte River Greenway. Credit: Denver Trolley
The Denver Trolley starts at Confluence Park in downtown Denver and hugs the Platte River Greenway. Credit: Denver Trolley


In 1887, American paleontologist, John Bell Hatcher discovered the mostly intact triceratops skull and horns and sent it to colleague, Othniel Charles Marsh. Marsh mistakenly thought the bones were from a bison, and they were not confirmed to be from a triceratops until the following year when another set of remarkably similar fossils was discovered in the area.   

The trolley trip to Lakewood Gulch combines history and paleontology with transportation geography. The current Denver Trolley system recalls the city’s once-extensive electric rail transit system. At its peak in the early 20th century, the trolley system had over 250 miles of track connecting the city and another 40 miles connected Denver to Golden and Boulder. In 1910, the system had 87,819,000 passengers.  


Map showing the Denver streetcar routes in 1917. Credit: Denver Urbanism
Denver streetcar routes in 1917. Credit: Denver Urbanism


Also in 1910, there were only 3,000 automobiles in Denver. After World War II, the American economy highly encouraged modernizing everyday life. By 1928, there were 78,000 privately owned automobiles and trolley ridership declined by 59%. By 1951, all the city’s trolley lines were abandoned and replaced by a new urban bus system.  

The Denver Trolley, a small section of that rail system, was later restored and reopened on July 4th, 1989, to revive some of the history and nostalgia along a route of some of Denver’s most popular attractions. The trolley runs Friday, Saturday, and Sunday from early spring to around Oct. 31. Tickets are $3 for adults and $2 for children. Other stops along the route include Confluence Park, REI’s flagship store, Elitch Gardens, and The Children Museum of Denver.   

Sources: Denver Trolley Colorado, Denver The Mile High City; “Dinosaurs in Denver,” Fossils Facts and Finds; “Triceratops Facts You Need to Know,” Denver Urbanism; “The History of Denver’s Streetcars and Their Routes”  

DOI: 10.14433/2017.0129


On the Map: Denver’s Five Points and Whittier neighborhoods

Image of Robinson Atlas of the City of Denver (Plate 12). Source: Denver Public Library, Special Collections
Image of Robinson Atlas of the City of Denver (Plate 12). Source: Denver Public Library, Special Collections

By Sam Hinton with Lisa Schamess

Northeast of downtown Denver, the Five Points and Whittier neighborhoods are among the city’s oldest, the first to extend beyond Denver’s original Congressional Grant. As a longstanding center for African American life in Denver, as well as a hub for the Chicano Movement, these neighborhoods are a vital location in the city.  

Five Points starts at 17th and Downing on the east edge and extends north along Downing to 38th Street. The Whittier neighborhood is less extensive, starting at 23rd and Downing Street and extending north until East Martin King, Jr. Boulevard. Established in the 1870s, Five Points was named after Denver’s diagonal downtown grid with a rectangular suburban grid, which meet at Washington Street, 27th Street, 26th Avenue, and Welton Street. Whittier Elementary School was named in honor of John Greenleaf Whittier (1807-1892), an American poet and abolitionist. 

The neighborhoods were and still are today dynamic and multi-cultural places. Many Latinx-Americans and Asian Americans work and reside in the area. While it was always historically a home to African Americans, increasing segregation in the 1920s resulted in more than 90% of Denver’s African American residents living in Five Points or Whittier during the mid-20th century.  

Throughout the 1930s, 40s, and 50s, the area was also a significant cultural and entertainment destination. The area is home to Denver’s first urban park, Colorado’s oldest Black church, and Temple Emanuel, one of the state’s oldest synagogues. Jazz also runs strongly through Five Points and Whittier’s narrative. Sometimes called the “Harlem of the West,” the area was a popular stop for jazz stars like Billie Holiday, Louis Armstrong and Miles Davis. They played clubs like the Rossonian and the Rainbow Room, and Benny Hooper’s hotel. Today, the annual Five Points Jazz Festival and Juneteenth Music Festival are renowned.  

The neighborhoods have a rich entrepreneurial history. For example, the Niederhut Carriage Company was a family-run business by brothers Henry and William Niederhut for a century, and one of the largest transportation manufacturing companies in Denver.  

In 1920, Dr. Clarence Holmes founded a dental practice at 2602 Welton Street and was the first African American to join the Denver Dental Society. A graduate of Howard University in Washington, DC, he otherwise lived his entire life in Denver. He was born to a family that valued civic responsibility: his mother Mary Holmes was the first African American woman to run for the state legislature. Dr. Holmes helped found the Colorado-Wyoming branch of the National Association for the Advancement of Colored People (NAACP). His early years as the first Black dentist in Denver were “rough,” he said in 1973, with obstacles put in his path by segregation, individual racism and intimidation, and white supremacist forces in professional societies and businesses serving dentists. Hear Dr. Holmes offer his oral history to the Denver Public Library in 1973 (Content Warning: frank use of racist terminology). 

Reverend David West Mallard owned multiple businesses including Mallard’s Grocery and Confectionery. Other notable businesses included Rice’s Tap Room and Oven, The Rhythm Records and Sporting Goods Shop, the American Woodmen’s Insurance Company, and Melvina’s Beauty Shop. 


Photo of Niederhut Carriage Company circa 1900; credit Denver Public Library Special Collections
Niederhut Carriage Company circa 1900. Credit: Denver Public Library Special Collections


Photo of David and Virginia Mallard in front of their store, circa 1948, with an unidentified man. Credit: Denver Public Library Special Collections
David and Virginia Mallard in front of their store, circa 1948, with an unidentified man. Credit: Denver Public Library Special Collections


Today, many descendants of the original Black residents no longer live in Five Points. Efforts to bring new life to the community have included a new urban rail line and the renovation of the Rossonian Hotel. These changes, however, have also accelerated gentrification, Nonetheless, the Five Points and Whittier remain an important touchpoint for Black and Latinx communities. The neighborhoods host many artists and are the center of several lively mural projects depicting their history and culture, such as La Serpienta Dorada and the Five Points Mural Gallery.  


Photo of Artist Brian Doss at the annual Jazz Festival in Five Points. Credit: Kent Kanuse, Flickr.
Artist Brian Doss at the annual Jazz Festival in Five Points. Credit: Kent Kanuse, Flickr.


Learn more: 

The neighborhood Business Improvement District hosts a self-guided, self-paced walking tour of Five Points. Five Points Plus is a museum and online exhibit that showcases the human stories and collective memory of living, working, and growing up in Five Points. Developed in partnership with the Black American West Museum and Heritage Center along with Five Points community members and supported by the Blair-Caldwell African American Research Library (Denver Public Library) and Manual Highschool. Prepare for your visit by finding out about the Black-owned and other businesses in the area. 

This article was prepared using sources from Denver.org and the Denver Public Library 

DOI: 10.14433/2017.0126


On the Map: The Spot Where Modern Denver Began

Confluence Park rapids and beach with a backdrop of the Denver Skyline by Kent Kanouse, Creative Commons
Confluence Park rapids and beach with a backdrop of the Denver Skyline by Kent Kanouse, Creative Commons

The confluence of two rivers in downtown Denver — Niinéniiniicíihéhe (the South Platte River) and Cherry Creek — marks the 1858 gold strike that launched a major city.

This spot also marks the prospectors’ encounter with the Arapaho, whose winter camping grounds and sovereign land this was, as affirmed in the 1851 Treaty of Fort Laramie. In addition to white settlers, Cherokee Nation citizens made up a significant number of the early prospectors, pushed off their own land after the 1828 Georgia Gold Rush and subsequent Trail of Tears.

At the site of Confluence Park, it was William Greenberry “Green” Russell who led the group that began a search for gold there in May 1858. When they found indications four miles south, their temporary settlement became what is now known as Denver.

In the intervening century, the 10.5-mile stretch of the South Platte River where Confluence Park rests fell on hard times, like many urban rivers. By the 1970s, it was a polluted, not only neglected but a frequent dumping site, “Denver’s receptacle for anything they wanted out of sight, out of mind.” according to Colorado State Senator Joe Shoemaker, who led the campaign to restore the riverfront. In 1974, Shoemaker co-founded the Platte River Development Committee with then-Denver Mayor Bill McNichols, eventually transforming it into the Greenway Foundation. The park underwent a long renovation and reopened with more amenities in 2018.

Confluence Park rapids and beach by Kent Kanouse, Creative Commons by Wally Gobetz, Creative Commons
Confluence Park rapids and beach by Wally Gobetz, Creative Commons

Today’s Confluence Park is a public gathering place that offers recreation, paved paths and nature trails, river views and natural landscapes; tubing, and a kayak run. Fishing is permitted, as are wading and shallow swimming at a small beach. Shopping and dining are close by.


Find out more about the Cherokee Nation’s participation in the Colorado Gold Rush

DOI: 10.14433/2017.0118

Sources: Colorado Encyclopedia; “Confluence Park,The Cultural Landscape Foundation; RIVER TOWNS: Denver | The South Platte’s dirty past promises a pristine future,” September 18, 2021 Colorado Politics; OsiyoTV; Uncover Colorado; “The Birth of Denver, from Boom to Bust to Boom,” Indian Country Today, Oct. 29, 2013. 


On the Map: The Wry Smile of Sable Island

Picture of Sable Island in an atlas.
Picture of Sable Island in an atlas.

When you next find yourself moving your eyes or navigating a finger across a map of the Northwest Atlantic, you may be in for a surprise. About 175 km southeast of Nova Scotia, a seam appears on the surface of the ocean and opens up, ever-so-slightly, into a wry smile. 

An adjacent label should offer a name: Sable Island.


Sable Island pictured in an atlas in isolation.
Sable Island pictured in an atlas in isolation.


Really? Can we be sure about this? The island is an anomaly, way out in the Atlantic, and there is nothing nearby that seems to justify its existence, geologically speaking. So it’s hard not to wonder about its position on the map, and its presence in the physical world. 

It is tempting to imagine that the island’s unusually graceful outline might indicate the presence of a clever cartographer — one who has inserted a fictitious landmass in the Atlantic to suss out copycat mapmakers. There are precedents for such behavior on land after all: Ever heard of a “trap street”?

But a quick internet search confirms that Sable Island does exist. It is a place of sand, wind, waves, a single Scots pine (the only survivor of more than 80,000 trees planted since 1900), and feral horses, among other things. 

Map of Sable Island
Map of Sable Island.


Looking closer, Sable Island yields quirks far better than any tricky mapmaker could. For starters, it looks like a barrier island but is located much further from the coastline than typical barrier islands. It likely formed from a terminal moraine — a mass of rocks and sediment carried down and deposited by a glacier, — sometime during the last Ice Age. That origin story may also help to explain the unexpected stability of some of the island’s dune structures. 

Over the last several centuries, Sable Island has also been notorious for attracting shipwrecks. Some 350 ships have succumbed to the sand bars, thick fog, and difficult currents characteristic of the area. Most of their remains have been crushed by waves and buried in the sand, making a full census impossible.


Sable Island map showing the location of the known wrecks upon the island
Sable Island map showing the location of the known wrecks upon the island.

Despite challenges of navigating to and from Sable Island, a rich history of research began there in 1871 with establishment of the Meteorological Service of Canada. Since then, research has expanded to include studies of climate, geomagnetism, and ecology. 

In 2013, Sable Island became protected as a National Park Reserve with the approval of Mi’kmaq stakeholders. Full national park status has yet to be achieved, pending settlement of Indigenous Peoples’ land claims within the Made in Nova Scotia Process.