Which explorers are primarily responsible for traveling through the inland part of the present the united states

Lewis and Clark

Explanation:

The Lewis and Clark Expedition, also known as the Corps of Discovery Expedition, was the first American Expedition to cross the western part of the United States. It travelled from Philadelphia to the Pacific Coast. These explorers were volunteers under the command of Captain Meriwether Lewis and Second Lieutenant William Clark. The main purpose of the expedition was to explore the newly acquired territory in the Louisiana Purchase.

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