Many discounts are available to seniors. Even if discounts aren't posted, ask if they're available. Seniors should always exercise caution in historic sites, where the ground can be uneven, and on cobbled streets in Edinburgh.

Members of AARP (formerly known as the American Association of Retired Persons), 601 E St. NW, Washington, DC 20049 (tel. 888/687-2277; www.aarp.org), get discounts on hotels, airfares, and car rentals. AARP offers members a wide range of benefits, including AARP The Magazine and a monthly newsletter. Anyone over 50 can join.

Many reliable agencies and organizations target the 50-plus market. Elderhostel (tel. 877/426-8056; www.elderhostel.org) arranges study programs for adults 55 and up. ElderTreks (tel. 800/741-7956; www.eldertreks.com) offers small-group tours to off-the-beaten-path or adventure-travel locations, restricted to travelers aged 50 and older. INTRAV (tel. 800/456-8100; www.intrav.com) is a high-end tour operator that caters to the mature, discerning traveler (not specifically seniors), with trips around the world that include guided safaris, polar expeditions, private-jet adventures, and small-boat cruises down jungle rivers.

Recommended publications offering travel resources and discounts for seniors include: The quarterly magazine Travel 50 & Beyond (www.trave150andbeyond.com); Travel Unlimited: Uncommon Adventures for the Mature Traveler (Avalon); 101 Tips for Mature Travelers, available from Grand Circle Travel (tel. 800/221-2610 or 617/350-7500; www.gct.com); and Unbelievably Good Deals and Great Adventures That You Absolutely Can't Get Unless You're Over 50 (McGraw-Hill), by Joan Rattner Heilman.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.