They are expensive to build, can't be done over a long span, and as they are usually built of wood, they burn down easily.
World Guide to Covered Bridges was created in 1953.
Susan M. Zacher has written: 'The covered bridges of Pennsylvania' -- subject(s): Covered bridges
Pittsburgh,PA ? No, and instead of WAG, try data. It's Texas by a long shot. http://obr.gcnpublishing.com/articles/nov05c.htm
Covered bridges were covered for a reason- they were made of untreated wood. The shed like cover kept rain and snow off the structural members, and made them last longer. When we began making bridges of steel, we no longer needed the covering.
Edwin Michelet Barton has written: 'The covered bridges of Columbia County, Pennsylvania' -- subject(s): Covered bridges
Pennsylvania has 197 covered bridges still standing statewide. Some you are unable to drive through, but many you can still drive through.
They were already formed but the were covered with water.
New Brunswick is home to approximately 60 covered bridges, making it a notable location for these historic structures in Canada. The province is known for its picturesque rural landscapes and charming covered bridges, some of which date back to the 19th century. These bridges are an important part of New Brunswick's cultural heritage and attract both tourists and history enthusiasts.
What traditional
There are 32 of them.
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Advantages and disavantages of parastatals companies