With consumers cutting back on everything from groceries to gas, spending on a vacation may seem downright frivolous. But opting to camp out in the backyard over hiking through the hills of Ireland this summer means you could be missing out on some extraordinary deals. Round-trip airfare to Ireland, for example, can now be had for under $500 -- less than half of what it would have cost last summer.

Thank all of those consumers who have been staying close to home for those deals. The Travel Industry Association projects that domestic leisure travel will decline by more than 2% this summer from last year. And travel abroad is expected to drop some 7% this summer. With so many empty rooms to fill, average daily rates at U.S. hotels are expected to be as much as 8% lower this year, according to Pricewaterhouse Coopers Hospitality & Leisure Practice. Cruise lines, meanwhile, are offering routes in the Caribbean routes that cost as little as $100 a day, says Kellie Pelletier, spokeswoman for Kayak.com, a travel search engine.

See 5 Places to Find Summer Travel Deals

Also helping to make summer travel even more affordable this summer: lower fuel prices. Airline fuel surcharges, which are tacked on to passengers airfare to offset high fuel prices, were as high as $170 and $460 for domestic and international flights, respectively, last summer. Now, fuel surcharges on domestic flights have been mostly eliminated and international surcharges are down to $220, says Tom Parsons, CEO of Bestfares.com, a travel price comparison site.

Here are some of the destinations that travelers can visit on the cheap this summer.

Many travelers who want to visit Australia don't because of the prohibitively pricey flights. But this summer, the biggest hurdle to getting to kangaroo country may just be the jetlag. (Also, keep in mind that our summer is their winter.)

Part of the reason: more competition. Virgin Blue launched flights to Australia this year and Delta will start flying to Sydney on July 1. Delta, for example, currently offers a round-trip flight from New York to Sydney (travel dates from July 18 to July 28) for $725. Last year, airfare ranged from $1,800 to $2,200, says Parsons.

Once travelers arrive they'll have a lot more buying power than last year. The U.S. dollar is almost 20% stronger than it was last summer compared to the Australian dollar ($1 equals 1.22 Australian dollars; last June $1 equaled 1.04 Australian dollars). Through July 30, a stay at the Hilton Sydney for at least two nights starts at $219 (U.S.) per night, a 50% savings.

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Whether you want to chill out on one island or cruise through half a dozen in a week, you can do so at a significant discount. Carribean cruise prices are down 10% to 25% over last summer, says Kayak.com's Pelletier. An interior cabin on a three-night Royal Caribbean Bahamas cruise departing from Miami on June 12, for example, costs $149 per person for the entire trip, a 33% discount to the normal rate of $224 per person.

If you stick to one island, then you'll find some of the biggest discounts at places like Puerto Rico, the Dominican Republic and the Bahamas, all of which have frequent flights directly to and from the U.S., says Pelletier. A five-night stay at the Gran Melia Hotel & Resort in Rio Grande, Puerto Rico in a garden view deluxe junior suite between June 17 and 22 costs $719 per person, including round-trip tickets from New York. Originally, the room alone would have cost $1,629.

Thanks to sky-high oil prices last summer, hefty fuel surcharges imposed on flights to Ireland made visiting the country a pricey proposition. But now the airlines have pulled back on those fees. Fuel surcharges on flights to Ireland from the U.S. have dropped from $270 last summer to a recent $14, says Parsons.

A round-trip flight from Dallas to Dublin, for example, leaving July 15 and returning on July 22 on American Airlines (and a transfer on Aer Lingus) costs $487. Last summer, the airfare would have been more than $1,000, says Parsons.

Once you arrive, you won't pay a premium price for hotels either. A stay in an executive room at the Fitzpatrick Castle Hotel in Dublin between June 25 and June 29 goes for a rate of $114 per night, down from $190.

Last summer, the weak U.S. dollar compared with the euro meant Europe was a no-man s land for budget-conscious U.S. travelers. But now the dollar has gained some ground. And while hotels are still expensive, they are nowhere near as painful as they were last year.

At the Melia Roma Aurelia Antica hotel in Rome, a four-night stay beginning on July 17 in a standard room costs 226 euros (or $321), down from 296 euros ($420), a 24% discount on the hotel price. Last year, a rate of 296 euros would have cost you $460.

A four-night stay in a double room at Hotel Nouvel in Barcelona, Spain in July costs 348 euros (or $494), down 27% from the original price of 478 euros ($679). Last year, 478 euros would have cost $743.

Direct flights to some of the more popular European summer destinations will still be a little pricey (one round-trip flight from New York to Rome on Delta, for example, costs $790), but there are ways to cut costs. Flights to Frankfurt, Germany are fairly cheap right now -- a nonstop Delta flight from New York to Frankfurt in mid-July costs $517.

Travelers can fly to Frankfurt and connect to Ryanair, which offers a flight from Frankfurt to Rome for five euros (or $7) and save 34%.

Don't feel like trekking overseas? U.S destinations that have been hit hard by the recession are offering great deals on lodging and other amenities. Rooms in Miami, for example, are going for half the normal rate, says Adrienne Chiron, president of Travel Trackers, a Florida-based travel agency. And in Las Vegas, where hotel occupancy rates are down more than 30% during the first quarter, travelers are snagging packages that include discounts at spas and restaurants, says Carl Schwartz, chief travel officer for CheapFlights.com, an airfare search engine. Here are some of the deals you can find:

Vegas: From June 28 through July 2, stay at the South Point Hotel Casino and Spa and pay $70 a night for a deluxe king room and get the second night free, breakfast buffet for two and 25% off a spa treatment. Offer must be booked by June 12, is available through Sept. 10, from Sundays through Thursdays.

Miami: Stay at the Chesterfield Hotel Suites & Day Spa in South Beach between June 9 and 11 and pay $89 per night for a junior suite. The regular rate: $120 a night.

Hawaii: Stay at the Aston Waikiki Beach Hotel in Oahu between June 12 and Aug. 23 and pay $129 a night for a standard room, a 37% discount off the original.