Terra-Marina in the 1960s; Sealander Today"

Here is a magazine blurb from the 1960s, which describes the above photo long before before the term "trailerable trawler" had been invented:

Magblurb

I'd be a bit concerned about weigh aloft myself, and just how do you get the car on and off, anyway?  This one makes more sense:

Ladies on TerraMarina

Terra-Marina disappeared from the marketplace a long time ago, but the idea was revived a few years ago by a German company. Sealander came along and reintroduced the notion of a combination camper-watercraft, usually shown powered by a Torgueedo electric outboard.

Sealander
Here's one magazine's review: The Sealander is a unique combination of trailer and amphibious vehicle. It is a caravan and yacht in one. High quality and aesthetics of boat-building are combined with the flexibility of a mobile home. It is dynamic and modern. The Sealander is an innovative lightweight mobile vehicle that is primarily a custom-made caravan but, with the help of a few handles and an outboard engine (any 5 PS long-shaft outboard engine will do) it turns into an amphibious vehicle. The best part is you don’t need any special license to operate the Sealander. Just slide it into the water and go fishing, swimming or whatever your heart desires. There are several features that will make your sailing even more enjoyable – a convertible sunroof, a telescopic element that can be used as a swim ladder, and a stainless steel handrail to ensure safe boarding.

Here's one magazine's review: The Sealander is a unique combination of trailer and amphibious vehicle. It is a caravan and yacht in one. High quality and aesthetics of boat-building are combined with the flexibility of a mobile home. It is dynamic and modern. The Sealander is an innovative lightweight mobile vehicle that is primarily a custom-made caravan but, with the help of a few handles and an outboard engine (any 5 PS long-shaft outboard engine will do) it turns into an amphibious vehicle. The best part is you don’t need any special license to operate the Sealander. Just slide it into the water and go fishing, swimming or whatever your heart desires. There are several features that will make your sailing even more enjoyable – a convertible sunroof, a telescopic element that can be used as a swim ladder, and a stainless steel handrail to ensure safe boarding.

Depending on options the price ranges from $17,500 to $19,500.

There's lots of romantic photography establishing the brand:

SEALANDER_pic_emotions_09
amphibious-caravan-SEALANDER_pic_emotions_08

There's only one problem that I can see.

sealander-camper

Where does one go to the toilet, if there's no place for a toilet? The swim platform is dual-purpose, you say. So much for romance!

But wait...Here's the answer from the same magazine review:

The Benches convert from generous seating (up to 6 adults) and dining to a spacious bed. The Sealander Caravan has storage below the seats and can even be customized to include a toilet, a cooler, a sound system or even a barbecue. Other features include a stainless steel wash and cooking module with cover plate, a single flame gas cooker, a tap with water pump, a 10-litre-fresh-water tank and a 10-litre-waste water tank, as well as a gas case and a fire extinguisher. With a closed sunroof, the Sealander is now your safe haven from wind and weather. Be it out on the water, or on dry land.  

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