What is the summary of "Composed upon Westminster Bridge"?

In "Composed Upon Westminster Bridge," the poet is crossing Westminster Bridge into London during the very early morning. Wordsworth loved nature, but finds the beautiful, clear scene of the London skyline spread before him while he crosses the bridge as quiet and lovely as anything to be found in nature. The city is serene in the early morning, not yet awoken. He marvels over how still it is. 

More specifically, in the first three lines Wordsworth says the city is so beautiful ("fair") that you would have to be a very callous person ("dull ... of soul") not to respond to its beauty. In the next two lines, he says the city wears its "silent" beauty like a garment laid on it. Its ships, domes and towers stand out "bright and glittering" in the clear air.

The next two lines note the sunlight falling as beautifully on the city as it would on any part of nature, be it rock, valley or hill. The poet shows his rising excitement over the stillness of the city in the last few lines. In line 11, he says he never saw or felt "a calm so deep!" and in lines 13 and 14, he again uses exclamation points as he notes the city's (he calls the city "that mighty heart") calm:

What is the theme of "Composed upon Westminster Bridge"?

Standing on Westminster Bridge, looking at London lying spread out on the horizon in the early morning sunrise, the speaker is moved by the beauty of the scene:

Never did sun more beautifully steep In his first splendour, valley, rock, or hill; Ne'er saw I, never felt, a calm so deep!

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What is strange about this poem is that Wordsworth, a Romantic poet who focussed so much on the beauty of Nature and the countryside, takes as his topic the city of London and treats it with a distinctly Romantic flavour. This sonnet praises the quiet and shimmering beauty of London in the light of an early morning. Throughout the poem Wordsworth uses personification to present the city and its houses and so on as humans, emphasising the peace of tranquility of his view:

This City now doth, like a garment, wear
The beauty of the morning...

The theme of this poem thus seems to be that cities can inspire similar feelings of "calm so deep" as Nature can, and in the final line, Wordsworth uses a paradox to present us with a final image of tranquility and silence:

And all that mighty heart is lying still!

Of course, hearts by their very nature never lie still, yet from his viewpoint, Wordsworth is able to imagine the "heart" of the country, London, "lying still" as he savours the peace and relaxation that the sight gives him. Such a poem allows us to see that Romanticism does not exclusively focus on Nature, and that similar themes can be found in poetry describing cities, which were normally seen as the anithesis of the simplicity and beauty to be found in nature.

What is the theme of "Composed upon Westminster Bridge, September 3, 1802"?

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"Composed upon Westminster Bridge, September 3, 1802" expresses the reflections of William Wordsworth as he looked out upon the glorious sights of the city of London visible from the bridge. Contrary to the impression given by the title, he probably did not compose the entire poem at one time; he may have begun it as he was leaving London in late July of 1802, finishing it upon his return on September 3.

At any rate, the poem recognized the magnificence and beauty of the still, quiet morning he beheld from his vantage point on the bridge. He observed "Ships, towers, domes, theatres, and temples" as he looked out and understood that it was possible to see them "All bright and glittering in the smokeless air" because it was early in the morning. He compares their grandeur to "valley, rock, or hill" and contends that "Earth has not anything to show more fair" than the sights of London.