The couple spent part of their trip admiring some classic art pieces at a variety of museums in the city, reported E!Online.
Klum, 27, posted a close-up photo of her profile on Twitter with Leonardo da Vinci's Mona Lisa behind her. She captioned the snapshot, "Looking at you.... Looking at me!"
After her split from her bodyguard-turned-boyfriend Martin Kristen , Klum and Schnabel were seen arriving at LAX on the same plane late last month, but weren't photographed together.