The de Young | Golden Gate Park, San Francisco, CA
From wikipedia:
The current building was completed by architects Jacques Herzog, Pierre de Meuron and Fong + Chan and opened on October 15, 2005. Structural, civil and geotechnical engineering was provided by Rutherford & Chekene; Arup provided mechanical and electrical engineering. Herzog & de Meuron won the competition in January 1999 beating out other short-listed architects Tadao Ando and Antoine Predock. The terrain and seismic activity in San Francisco posed a challenge for the designers Herzog & de Meuron and principal architects Fong & Chan. To help withstand future earthquakes, “[the building] can move up to three feet (91 centimeters) due to a system of ball-bearing sliding plates and viscous fluid dampers that absorb kinetic energy and convert it to heat”.[9]
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The designers were sensitive to the appearance of the building in its natural setting. Walter Hood, a landscape architect based in Oakland, designed the museum’s new gardens. The entire exterior is clad in 163,118 sq ft (15,154.2 m2) of copper, which is expected to eventually oxidize and take on a greenish tone and a distinct texture to echo the nearby eucalyptus trees. In order to further harmonize with the surroundings, shapes were cut into the top to reveal gardens and courtyards where 48 trees had been planted, the giant tree-ferns that form a backdrop for the museum entrance are particularly dramatic. 5.12 acres (20,700 square meters) of new landscaping were planted as well, with 344 transplanted trees and 69 historic boulders. The building is clad with variably perforated and dimpled copper plates, whose patina will slowly change through exposure to the elements. This exterior facade was developed and fabricated by engineers at Zahner.[10] A 144 ft. (44 m) observation tower allows visitors to see much of Golden Gate Park’s Music Concourse (see below) and rises above the Park’s treetops providing a view of the Golden Gate and Marin Headlands.
The twisting 144 foot (44 m) tall tower is a distinctive feature, and can be seen rising above the canopy of Golden Gate Park from many areas of San Francisco. The museum offers a two-floor museum store, free access to the lobby and tower, and a full-service cafe with outdoor seating in the Osher Sculpture Garden. The executive chef is Lance Holton.
Read more about The de Young museum
not part of any exhibit or display, just happened upon a flower on top of this block in the foyer area before entering the museum: 
next visit, maybe later in the year, California Science Center
( view from The de Young museum’s Hamon Tower )
alaundre 
Looks like a rock, pleasant horizon pollution 😉 (and great pics as usual)