The keyword term "September 11th National Memorial Trail" functions grammatically as a proper noun. As a multi-word proper noun, it serves as the specific, capitalized name for a unique geographical and commemorative entity.
In this compound nominal phrase, the head noun is "Trail." The preceding words"September 11th," "National," and "Memorial"act as adjectival modifiers that specify the trail's identity. "September 11th" is an attributive noun phrase identifying the historical event, while "National" and "Memorial" describe its scope and purpose, respectively. This sequence of modifiers progressively narrows the reference from a general trail to a specific, named one.
Recognizing the phrase as a proper noun is crucial because it treats the entity as a singular, officially designated place. This grammatical classification dictates its capitalization and ensures it is understood not as a descriptive category of trails, but as the unique name for the 1,300-mile system of trails and roadways. This distinction is vital for clear communication in cartography, legislation, public discourse, and digital indexing, ensuring the trail is uniquely identified as the route connecting the World Trade Center, the Pentagon, and the Flight 93 National Memorial.
