Nothing will plunge you into a holiday mood faster than touring the Hudson Valley of New York State, a hotbed of palatial mansions built in the Gilded Age. Today, many of these showplaces are open to the public and are especially worth visiting during the holidays, when they deck the halls to the hilt and make you feel instantly festive (and, yes, the teeniest bit humbled at your relative lack of square footage).

We recently checked out Mills Mansion in Staatsburgh, decorated to re-create a 1907 holiday season wedding. Both of my girls were amazed by the 25-foot-high tree dripping with ornaments and spanning two stories of the reception hall. My 7-year-old, Elizabeth, commented that this would be a great place to play hide-and-seek (her favorite method for exploring a house, regardless of furnishings and aesthetics). She also kept asking repeatedly if someone really had lived here. Yes, once upon a time, people really did live this way, I informed her. Yes, the children really did have their own servants bringing them cake at their very own table. Don't get any ideas!

Over the next few weeks, we plan on visiting many other architectural landmarks. Entertainment, workshops, and candlelight tours are part of the draw. If you're visiting New York City for the holidays, it's worth a field trip up the river to see how the rich once escaped big city life. Some of the websites have train travel tips. From north to south, here's our must-see list:

Wilderstein www.wilderstein.org

Staatsburgh State Historic Site (Mills Mansion) www.Staatsburgh.org

Vanderbilt Mansion Historic Site www.nps.gov/vama/

Locust Grove www.morsehistoricsite.org

Boscobel www.boscobel.org/

Van Cortlandt Manor www.hudsonvalley.org

Washington Irving's Sunnyside www.hudsonvalley.org