Head for the rambling byways of Rancho Santa Fe.

If outdoor exercise is part of your New Year's resolution, perhaps it's time to pull your ten-speed or mountain bike out of cold storage in the garage and head for the rambling byways of Rancho Santa Fe. Unlike other high-priced residential communities, this one does not cower behind locked gates. While freely traveling its curvilinear back byways, anyone is free to espy an unremitting succession of perfectly tended landscapes, whitewashed fencing, discreetly sited homes, decorative crops, and pseudo-Australian forest.

Three million eucalyptus seedlings were planted on the scrub land of today's Rancho Santa Fe a century ago to provide wood for railroad ties, a project quickly abandoned when eucalyptus wood was proved useless for virtually any structural use. Some of the original trees remain today, along with younger trees, helping to blanket the community's hills and dales with cool semi-shade.

When traveling by bike here, avoid the weekday morning and afternoon commute times, when traffic backs up on the arterial roads. Sunday mornings find the roads nearly deserted -- and so, too, Super Bowl Sunday, during the game itself. Be prepared for moderate but nearly constant elevation changes. Any bicycle with low gears and good brakes will suffice to tackle them.

Two suggested loop routes, of 11 and 4 miles, are arrowed on the accompanying map, which has many but not all through-streets plotted. Both loop routes begin at the small, Spanish-styled business district near La Granada and Paseo Delicias. Try either route, or improvise your own.

The 11-mile loop takes you up and over several ridges and swings around San Dieguito Reservoir, a fenced storage facility for municipal water. The up and down grades aren't steep, except for Rambla de las Flores and Calzada del Bosque near Linea del Cielo.

On the shorter eastern loop, 4 miles over La Valle Plateada, El Vuelo, and Las Colinas, you'll be out in the sunshine most of the time. Expansive views extend to the east -- miles of rolling hills backed by distant mountains, as far as the eye can see.