The Eureka Zeppelin was a passion project to bring a commercially sustainable zeppelin to California for recreational use. Monetization to fund the flights of the largest zeppelin in the world by volume included advertising and making the airship available to scientists to whom the unique flight characteristics of such a craft were particularly conducive to their area of study. And if you saw Disney/Pixar's animated film, Up, the "evil" zeppelin's engine and propeller sounds were recorded directly from Eureka's engines.
These images were taken on one of several trips that Eureka took between Moffett Field and Long Beach, flying for about eight hours between one thousand and a few thousand feet above the California coastline.
Unfortunately, Eureka has since been dismantled and returned to Germany after profitability became unsustainable. To this day, only a handful of pilots are even certified to fly such a craft.