Lines Composed a Few Miles above Tintern Abbey, on Revisiting the Banks of the Wye during a Tour, July 13, 1798 Contrasting Regions Quotes

The first lines describe how long it's been since the speaker's first visit to the river Wye, but they also suggest, through the repetition and emphasis on how long those years felt, that those years were not spent pleasantly. We learn later in the poem that at least some of that time was spent in the city, far from the river Wye, and far from natural beauty of any kind.

Even in the middle of the noisy city, the "beauteous forms" of the Wye river valley were present in the mind's eye of the speaker.

The city feels "lonely" to the speaker, even though there are more people than in the country. He also emphasizes the distracting "din," or noise of the city.