Marina Abramović is perhaps the world's best known performance artist, but she wasn't always so famous-in the 70s and 80s she and her lover, fellow artist Ulay, pushed the boundaries of the fledgling field where they would both thrive for decades to come.

Although art may last an eternity, love may not, and in 1988, in their final project together, they each started from opposite sides of the Great Wall of China until they met in the middle, for one last embrace.

Then came Ulay's turn. When she raised her head to gaze at the next stranger, the emotions and tears of that reunion were captured on film and became a powerful ode to lost love. It is hard to watch without crying.

Here's the video, with music for the moment created by How I Became The Bomb… (Story continues below.)

28 million people have been captivated by the romantic music video on YouTube, but the succeeding years have been less romantic.

The two became adversaries in a legal battle over rights to their earlier work, but this moment in 2010, during her installment called, The Artist is Present, may be their most enduring and priceless performance.

Have Your Friends Seen This? Click to Share…. (Photo by MoMA)