Fergie and Josh Duhamel are getting married tomorrow ...and only Radaronline.com has found the secret location of the wedding!

In this exclusive video you can see tents behind the walls of a multi-acre estate and a security guard keeping watch as preparations ae underway.

More than 75 guests will be bused to the site of the ultra-private ceremony, which will take place near the ocean outside of Los Angeles.

The centerpiece of the estate is a 8,000 square foot French chateau, which is surrounded by gardens and vineyards. Inside, rooms are furnished with French antiques and panoramic views of the surrounding countryside.

Guests will also enjoy a 500-foot stream that flows over two waterfalls before feeding into a small lake.

There, visitors will find a cozy, rustic lakeside boathouse.

We've given our competition enough hints to try and find the location, but you can see it here first!

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