beautiful spring cherry blossoms washington pink white lined tidal basin thomas jefferson memorial background clear blue sky usa american america landmark states reflection united monument travel lake historic flowers blossom national tourism springtime flower skyline colorful trees season water river color april district symbol tree patriotism columbia history potomac george festival mall close shot crowd people steps memoril building architecture capital famous place attraction dome politics sightseeing culture city vacation sunrise capitol illuminated president bloreflection washington dc memorial usa monument american jefferson travel tourism landmark thomas historic national architecture history capital famous water patriotism america reflection place attraction states dome united tidal basin district columbia politics spring sightseeing culture city symbol building vacation sunrise capitol illuminated president