* Abdicating Dutch queen says son ready to take crown
* Amsterdam awash with orange, people prepare to party
* Royals popular, but roles mainly symbolic
Willem-Alexander will become the first King of the Netherlands in more than 120 years when Queen Beatrix passes the crown to her eldest son on Tuesday morning.
"He's ready, in every way," Queen Beatrix said of her 46-year-old son, a water management specialist who is expected to bring a less formal touch to the monarchy, as she bid farewell to the nation in a subdued televised address on Monday night.
April 30, or Queen's day, is always a day for partying in the Netherlands, although many Dutch took Monday off work and started celebrating in earnest from Monday evening with street bands and music.
But this year the city of Amsterdam is putting on a special show to celebrate the investiture of Willem-Alexander and the abdication of Beatrix, 75, who wants to retire after 33 years in the job.
The royals are broadly popular, with 78 percent of Dutch in favour of the monarchy up from 74 percent a year ago, according to an Ipsos poll.
But they have been stripped of their political influence, and no longer appoint the mediator who conducts exploratory talks when forming government coalitions.
Amsterdam is already awash with orange, the royal colour. Houses are covered in bunting and flags, shop windows are stuffed with orange cakes, sweets, clothes and flowers and many partygoers are decked out in the royal colours.
Nearly a million people are expected to join the street party with dancing to bands and DJs, helping create a carnival atmosphere. As always, there will be people on the pavements at dawn setting up traditional makeshift bric-a-brac stalls.
RARE TRIP BY JAPAN'S PRINCESS
Britain's Prince Charles and Japan's Crown Princess Masako, who is making her first foreign trip since falling ill a decade ago, will be among 2,000 visitors at the official ceremony.
"There will be tears on Tuesday," said Dutch Prime Minister Mark Rutte, paying tribute to "this formidable lady who has ruled this country for over 30 years". ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ New King of Netherlands will reign with clipped wings ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
On Tuesday morning at 10:00 a.m. (0800 GMT) Beatrix will sign her abdication, whereupon Willem-Alexander immediately becomes king and his wife Maxima, a popular former investment banker from Argentina, becomes queen.
All three will appear on the palace balcony to wave and address the crowds in Dam Square.
They will then head from the palace to the 600-year-old Nieuwe Kerk, or New Church, next door where the king will swear an oath to uphold the Dutch constitution before lawmakers.
The Dutch monarch is never crowned, since, in the absence of a state church, there is no cleric available to carry out the coronation. But there is a crown, which will sit on a table next to him throughout the ceremony, along with other regalia that constitute the crown jewels.
Willem-Alexander will wear a royal mantle that has been used for investitures since 1815, although it has been repaired and altered at least twice over the past century, for the investitures of his mother and grandmother.
The celebration will continue through the evening with a water pageant along the Ij, Amsterdam's historic waterfront.