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TechnoTourist’s Engineering Expeditions

Want to travel the world, but don't have time to leave the office? TechnoTourist is here to save the day! Tag along while TechnoTourist visits famous engineering feats around the world. TechnoTourist will also investigate fascinating technologies that help to preserve and discover incredible travel locations. Maybe you could use TechnoTourist's insights to help you plan your next travel itinerary, or escape from the stresses of everyday life!

Paris's Sewer System

Posted June 10, 2016 12:00 AM by joeymac

I’ve just returned from a trip to Europe and one of my stops was in Paris, France. We got poured on pretty good there, but I must admit that I feel lucky since we missed out on the Paris floods and were able to walk around and enjoy the sites. One of the things that I learned while on a tour that amazed me was that the city to this day cleans and unclogs its sewers out with giant balls of iron. The French call them “boules de curage.” Models of these iron and wood balls can be seen on display at the Paris Sewer Museum (Musee des Egouts de Paris).

This technology has been around since the 1850’s when Paris modernized its sewage system under engineer Eugene Belgrand. These iron balls or orbs, which measure 10 to 15 feet in diameter, slam into the refuse, knock it free, and restore flow. These orbs are using a lot of velocity and with their sheer size cut through the refuse like a hot knife through butter. They act like a drain snake for a clogged kitchen sink. They are used roughly every six months or whenever there’s a clogged sewer line. These balls vary in size to fit the assorted old tunnels which are not uniform in size.

22 comments; last comment on 06/15/2016
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Vacation Destinations for Engineers

Posted July 17, 2014 9:13 AM by SavvyExacta
User-tagged by 1 user

What are your summer vacation plans? TechnoTourist has compiled a list of some destinations of engineering interest that have been featured on the blog in past years. Please add your suggestions in the comments!




11 comments; last comment on 07/22/2014
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Castell de Bellver - Mallorca Spain's Circular Castle

Posted November 02, 2013 12:00 AM by SavvyExacta

Bellver Castle, or Castell de Bellver, is located in Palma de Mallorca and dates back to the 14th century. This particular castle is unique because of its round shape, the only one of such a design in Spain.

Circular Design

Bellver Castle was built from 1300 to 1311. The structure combines many defensive elements with palatial design:

  • Two-story castle in a circular shape
  • Hilltop location with 360 degree views of the ocean and surrounding mountains
  • Moat surrounding the structure
  • Three small towers connected to the main structure
  • A fourth large tower, called a keep, connected by a bridge
  • Open courtyard with well or cistern at the center
  • Various rooms off the courtyard with gothic arches

The sandstone used to construct the castle was taken from nearby rock quarries. The four towers face the four points of the compass with the largest tower, the keep, facing north.

Uses of Castell de Bellver

The original purpose of the castle was to serve as a summer home for the Kings of Mallorca. The castle did not see much battle action; it resisted two sieges during the Middle Ages.

The castle was first used as a prison in the 14th century and that was also its primary function during the War of Spanish Succession and the Spanish Independence War. It served as a political prison as recently as the mid-20th century.

Today the castle is a museum. Some aspects of the building have been modernized: for example, glass now fills some of the arrow slits. Modern conveniences like handicap access ramps and restroom facilities have been added.

Still, the castle is well-maintained and largely mimics its original design. Etchings made by prisoners can be seen in the walls. The views from the top of the castle are stunning. For the views alone, the castle is worth a visit. The fact that you're taking in such views from the top of the castle is just the icing on the cake!

True castle enthusiasts can even purchase a Bellver Castle Model Kit.

Read about my visit to Barcelona.


Castell de Bellver - Museum d'Historia de la Ciutat

Wikipedia - Bellver Castle

North South Guides - Mallorca Bellver Castle

Destination360 - Castell de Bellver

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Barcelona and the Influence of Antoni Gaudí' (Park Güell, Sagrada Familia)

Posted October 11, 2013 12:00 AM by SavvyExacta
Pathfinder Tags: Gaudi Park Guell Sagrada Familia

My travels brought me to Spain a few weeks ago. Barcelona is a port city that was revived by hosting the 1992 Summer Olympic Games. But 100 years before those Games, the city's architecture was influenced by the work of Antoni Gaudí, who made Barcelona his home. You can read more about Gaudí at the Gaudí House Museum website, but Wikipedia has even more information.

Gaudí's designs are known for incorporating his passions of architecture, nature, and religion. He began implementing modernista, neo-Gothic, and naturalist designs in Barcelona in the late 19th century. Eusebi Güell, a Catalan entrepreneur, commissioned many of Gaudí's works.

Here are some of his most famous and recognizable designs in the city of Barcelona.

Park Güell

Gaudí began work on Park Güell in 1900 and continued through 1914. The space was originally intended to be an upscale housing development in a park setting. The housing plan failed after two structures were built. Today the area is a municipal garden. It's very unique! Mosaic art and whimsical walkways flow throughout the park. Built on a hillside, a series of ramps and staircases wind their way to the top. The park was intentionally designed without roadways to minimize intrusions.

Casa Batlló

image credit -

Casa Batlló was constructed from 1904-1906. This well-known house has a unique façade. Gaudí did not like straight lines and so incorporated other design elements into the house:

  • The balconies are designed to look like masks
  • Colored ceramic fragments tile the front
  • The roofline is arched and resembles a dragon's back

Casa Milà

Constructed from 1906-1910, Casa Milà is another house with unique design elements:

  • The top of the house is meant to look like a snowy mountain
  • The chimneys are shaped like medieval helmets
  • The façade and balconies were inspired by waves and seaweed

Sagrada Familia

Construction of the Sagrada Familia began in 1882. Gaudi's involvement began in 1915; the church is his most famous work and will not be completed until at least 2027. After Gaudi's death in 1926 (he was struck by a tram), construction has continued to his specifications despite some difficulties. Gaudi primarily used models, rather than blueprints or plans on paper, to communicate his design. Many of his models for the Sagrada Familia were destroyed during the Spanish Civil War.

The Sagrada Familia is unique in many aspects of its design and is intended to imitate natural shapes. In fact, it's supposed to look like a forest, and it does when viewed from a small park across the street. At completion it will have 18 towers.

Three facades of the church depict different parts of the Bible. Gaudí completed the Nativity façade before his death. This video shows what the finished church will look like. Improvements have come along more quickly since 3D design software, modern cranes, and lifts replaced mechanical tools and wagons!

1 comments; last comment on 10/11/2013
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The Secrets of the Mojave Desert – A Land of Wonder and Mystery

Posted July 20, 2013 12:00 AM by johngower

The Mojave Desert, located in southern California and Nevada, is the smallest of the North American Deserts. The Mojave is bordered by the Colorado River to the east and the Sierra Nevada Mountains to the west. The mountain range's rain shadow effect creates the Mojave's arid climate, with the desert averaging annual rainfall totals of between 2.23 and 2.5 inches a year - mostly in the winter season from October to March. The Mojave is classified as a "high desert" with an elevation between 2,000 and 5,000 feet. The desert's temperatures vary widely depending on location; the Mojave is a cold desert in the northern section and a hot desert in the southern. Temperatures plummet as low as 8 degrees Fahrenheit in January and exceed 119 degrees in August.

The Mojave contains a unique series of dune fields, the largest of which being the Kelso Dunes. These monumental mounds of sand are up to 600 feet in height, containing eolian sand deposits with a high content of quartz and feldspar. These dunes, sprawling over 45 square miles, are a relatively small part of a sand transport system that includes nearby Devil's Playground.

The Mojave Desert ecosystem places extreme stresses on its inhabitants - extreme temperatures, extremely small amounts of precipitation, lack of shelter or shade. Because of the unique biome, many of its plants and animals have adapted with strategies to survive its stresses. Mojave plants - including brittlebrush, creosote bush, Joshua trees, and sagebrush, among others - tend to have shallow root systems that allow for quick absorption of rain, spines and waxy leaves to help retain water, and thorns which protect their retained moisture from opportunist predators. The singularity of the ecosystem makes for distinctive plants - for instance, the Mojave is the only place that the Joshua tree is found in the world. The Joshua tree, a large, woody monocot, is itself is a glimpse into past eons as a plant that bridges the gap between grasses and more vascularly complex flora.

Animals have likewise adapted to the Mojave's harsh conditions. Desert tortoises, for instance, can store up to one quart of water in their bladder, to be re-circulated through their body in small amounts. Tortoises - and many other animals, including coyotes and rattlesnakes - burrow into the sand to avoid the sun's heat. Tortoises can spend as much as ninety-five percent of the their life underground.

The US Geological Survey has determined that the Mojave's climate is far from static, with precipitation increasing since the early 1970s. Changing weather patterns are likely going to affect the Mojave's vegetation, and possibly cause the desert's borders to shift over the next few hundred years.

Editor's Note: John Gower is a writer for NerdWallet, a personal finance website dedicated to helping you save money with financial tips on everything from travel to online stock trading reviews.

Image Credits:,

4 comments; last comment on 07/24/2013
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