Washington (CNN) Justice Ruth Bader Ginsburg revealed Tuesday that she traveled with retired Justice John Paul Stevens "in the last week of his life" to Lisbon, Portugal, for a conference where the two justices attended meetings, visited museums, vineyards and castles.

"Perhaps he knew at age 99, distant travel was a risk," Ginsburg said during Stevens' funeral at Arlington National Cemetery , "but he wanted to experience fully the joys of being alive, and he did just that almost to the end."

Ginsburg, 86, said that as the "next eldest in attendance" she had the opportunity to ride with him on long drives and his mind "remained vibrant" and he spoke not only of court cases but footnotes in various opinions.

"His conversation was engaging, his memory amazing," she said. As they were leaving the US ambassador's residence during their last evening in Lisbon, Ginsburg told Stevens, "My dream is to remain on the court as long as you did."

His immediate response, she said, was "Stay longer!"

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