The Hart Senate Office Building is currently the site of a significant restoration project involving 'Mountains and Clouds,' a large-scale sculpture created by renowned artist Alexander Calder. The installation, which dominates the building's atrium, is a staple of the Senate's art collection.

While the sculpture has been a permanent fixture in the building, this restoration effort marks a notable departure from its previous static state. According to reports, the project will introduce a mechanical upgrade that enables the mobile portion of the artwork to move. This change is intended to realize the artist's original vision for the piece, which has remained stationary since its installation. The restoration is being framed as a cutting-edge update to one of the most recognizable pieces of art within the Capitol complex. Work is currently underway to ensure the structural integrity of the mobile while integrating the new movement capabilities. No specific timeline for the completion of the project or the total cost of the restoration has been publicly detailed in initial reports, though the effort is being treated as a major maintenance and preservation milestone for the Senate's artistic assets.