Travel: Echoes of the Age of Innocence: Rhoda Koenig discovers the grand mansions of the Hudson River valley, built as havens for 19th-century New Yorkers

AFTER a rough week in the city, it's natural to want to spend a weekend in the country unwinding, especially if the city is New York and you're engaged in the gruelling business of sightseeing. If you are exhausted after several days of shopping, theatre-going, museums, restaurants and nightclubbing, why not head for the place New Yorkers themselves go for a rest and a glimpse of more greenery than they see on their salad plates?

Due north of New York city, the Hudson River valley offers dramatic, densely wooded scenery that has changed very little since the white men came (the paintings of the 19th- century Hudson River School still make reliable postcards) and has a string of stately and charming homes to visit. All are located on or slightly off Route 9, so there's no need to make complicated plans or worry about directions.

The difference between country houses in New York state and Britain is that, instead of being the family's seat and source of wealth, the American houses are the family's retreat from its base in the city. Robber barons who had made their pile on Wall Street and built a huge mansion on Fifth Avenue would erect a smaller, more informal one up the river, within easy yachting distance. The first such house on the drive north is Lyndhurst, the home of the railroad magnate Jay Gould.

Lyndhurst represented the Goulds' escape, not just from the business of the city, but from their century. An exquisite Gothic fantasy, the house shows off the family's medieval mania, with stained-glass windows, a great hall with a minstrel gallery, Gothic bedroom suites and, in the bathrooms, Gothic shower heads. Part of the house, however, is authentically period - one of the Gould daughters became the Duchess of Talleyrand-Perigord and returned from Europe with enough 15th-century French furniture to fill the rooms she used on her visits.

For all its tributes to the past, Lyndhurst carries the heavy stamp of the wealthy late 19th-century man of business. A monumental sofa, guarded by lowering carved lions, has a built-in humidor; Gould's desk ingeniously separates and divides, like a folding trunk, and has its own mail slot. And though the Goulds, like all such families, had a surplus of pretty gilt clocks, the timepiece that makes the biggest impression is one set into an object that couldn't be more down-to-earth: a large, brass scale model of the St Louis YMCA.

At Hyde Park, the birthplace of Franklin Delano Roosevelt, the house itself - a comfortable 1860s mansion furnished by old New Yorkers with no taste or desire to show off - is not the main attraction. The Roosevelt Library/ Museum, however, is a fascinating collection of Americana, exhibiting not only photographs, letters and contemporary cartoons, but also the assassin's bullet that, meant for FDR, killed the Mayor of Chicago. The collection also displays the 1936 open-topped Ford Phaeton and a case devoted to FDR's 'little dog Fala', with the Scottie's collars and a tag reading: 'Please return me to the White House'.

One room movingly documents the suffering of the Depression and Roosevelt's efforts to relieve it, including a wall devoted to the Hundred Days, the beginning of FDR's first term, when he completely changed the nation's banking and social welfare systems. Hyde Park is Roosevelt's resting place as well, and that of Eleanor Roosevelt. A gap in the hedge of the rose garden leads not to the huge marble monument that one expects but to a grave of shocking simplicity: two grass-covered mounds, one topped by a small American flag.

On a side road just two miles from Hyde Park is Val-Kill, where Eleanor Roosevelt had her own retreat from the cares of state and from FDR's overbearing mother. With two women friends who lived there, she set up a furniture factory, and after her husband's death it became her home for the rest of her life. In the small, endearingly frumpy cottage she received such visitors as Nehru, Khrushchev and John F Kennedy, and the house is full of mementoes of the grand visitors as well as of the great First Lady. Unfortunately, the spirit of females in charge is rather unattractively preserved by the bossy wardress who herded our mandatory group tour, delivering stern lectures on orderly behaviour.

A couple of miles further upriver, the 50-room Vanderbilt mansion displays the drive to instant tradition of a very rich and very nouveau family. To furnish the house, which the Vanderbilts used for only a few weeks in the spring and autumn, Europe was ransacked for coffered ceilings, Renaissance chairs and rococo gilt panelling. The intimidating magnificence drives one down to the kitchen and servants' quarters in search of some humanity, but there one is impressed all over again by the Vanderbilts' lavishness and their insistence on fitted, fully functioning perfection. (While the upper floors are a museum of super-rich 1890s taste, the basement is a true museum of kitchen technology.) The grounds are beautifully and dramatically landscaped, illustrating Moss Hart's comment about another magnificent country estate: 'This is what God would do if he had money.'

Montgomery Place, named after the first general to be killed in the American Revolution, is a much friendlier and more domestic house. An 1805 Federal building, 'modernised' in the 1860s with a Gone With The Wind- style portico, it contains many fine American antiques, portraits and the relics of nearly 200 years of occupation by a single family. There are many subtle touches: the Bohemian glass light fittings in the dining room are in the shape of morning glories to match the floral wallpaper. The extensive grounds hold the remains of a 19th-century arboretum, as well as a series of orchards where visitors can pick peaches in the summer and apples in autumn. Bring some cotton wool, though, to protect yourself from the spiel of the tour guide.

The high point, in more than one sense, of a trip up the Hudson is Olana, home of a prominent Hudson River School painter, Frederic Church. In the 1870s, a decade after Leighton House was built, Church designed his own Victorian Moorish villa on top of a hill, where he looked down through pointed arches on his pictorial subject matter. The furniture and decorations are a rich mix of fancy fretwork, damascene tiles, Oriental rugs, Chinese vases, Indian imitation-ivory chairs and bronze peacocks, and the walls are hung with Church's glowing landscapes and biblical scenes, an essential stop for any admirer of Victorian exotica and flamboyance.

If you want a more rugged outing, or have children to entertain, you can get a different taste of Victoriana at the Mohonk Mountain Lodge, just over the river in New Paltz. This hypertrophic Swiss chalet on a private lake, sprouting verandas, nooks and little twiggy bridges and bowers at every turn, has been managed by the same family since 1869, and offers golf, riding, tennis, swimming, boating, trout fishing, ice skating, cross-country skiing and biking through the hotel's 7,500 acres of hills and forests. You can stay at Mohonk at a rate that includes four meals a day or simply book a lunch, which entitles you to use the hotel's facilities. The buffet is served in an immense, magnificent octagonal room, a cross between a barn and a cathedral, but the food could most favourably be described as 'filling'.

If you make a very early start, it's possible to see quite a few places along the Hudson in a day, starting with Hyde Park or the Vanderbilt Mansion, which opens at 9am. If you'd rather make a weekend of it (the Mohonk Mountain Lodge will not accept a single-night booking at weekends), the town of Rhinebeck is the best place to stop. Settled by the Dutch in 1686, it still retains a good deal of low-key charm, and with its streets of eccentric Victorian timber houses, it is something of an outdoor museum.

The Beekman Arms (1766), which rather loudly proclaims its status as the oldest hotel in America, has the best food for many miles around - a sophisticated version of classic American cooking - but it is cheaper and quieter at its annexe, the Delameter House, a Hansel and Gretel building by the architect of Lyndhurst. The Red Hook Inn, in the next town, is a friendly converted Victorian house with period furnishings, a lively bar and, on our visit, a dinner of clam chowder, lobster, vegetables, salad, coffee and pie for dollars 7 ( pounds 4.80).-

TRAVEL NOTES

GETTING THERE: American Airlines (081- 572 5555) has an Apex fare to JFK, booking 21 days in advance and flying midweek for pounds 356, plus about pounds 14 tax. Virgin Atlantic Airways (0293 747747) has flights to both JFK and Newark departing Heathrow pounds 334 midweek, pounds 367 weekend; prices are the same for high season beginning 15 June. (All prices are subject to change). STA (071-937 9971) has flights from Heathrow to New York from pounds 230 return until the end of June.

STAYING THERE: Mohonk Mountain Lodge, tel: 914 255 4500; Beekman Arms, tel: 914 876 7077; Red Hook Inn, tel: 914 758 8445. For descriptions, see main text.

CAR HIRE: Eurodollar (0895 233300) offers an economy-size vehicle at a weekly rate of dollars 192 ( pounds 132), next size up dollars 226 ( pounds 156). Hertz (081-679 1799) provides an economy car at a weekly rate of dollars 199 ( pounds 137); damage excess is dollars 100 ( pounds 69) and state tax 10-13 per cent.

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