(CNN) — Tourism backlash has been in full effect over the past 12 months, with several destinations announcing they'd had enough of foreign visitors flooding their streets or disrupting their fragile ecosystems.

Unsurprisingly, this has posed a a dilemma for mindful travelers planning their next vacation.

From Venice and Barcelona to the Galapagos Islands and even the Taj Mahal, here are 12 places conscious tourists might want to think twice about visiting in 2018:

1. Isle of Skye, Scotland

The Isle of Skye has been struggling with increasing numbers of tourists. Jeff J Mitchell/Getty Images

In 2017, the infrastructure of Scotland's largest island creaked under the pressure as thousands of tourists in coaches and cars plied its narrow lanes, making a beeline for the remote fairy pools at Glenbrittle, the iconic sunset spot at Elgol and the rocky Old Man of Storr, with traffic snarl ups an inevitable result.

Eventually the residents of beautiful Skye said enough was enough after complaints of noise, overcrowding and even visitors urinating in public.

Police advised visitors to stay away unless they had already booked places to stay.

If you must go then ...

Visit outside the summer season, when tourist numbers drop and iconic sites can be explored without having to battle crowds.

Alternatively ...

Explore the Small Isles of Rum, Muck and Eigg or go south and get lost on Jura.

2. Barcelona, Spain

Barcelonians have been protesting against tourist overcrowding. Josef Lago/AFP/Getty Images

The Catalan capital saw 34 million tourists visit in 2016, a 25% jump from 2012. This has led to anger from locals, with anti-tourist graffiti emerging across the city.

Protesters even stormed the beach at Barceloneta in August 2017, decrying rowdy behavior as well as those using the sand to sleep off a night on the sangria.

Residents say services like Airbnb have sent rents soaring, forcing them from their homes. However the city's government has passed a law to limit tourist beds in a bid to tackle the problem.

If you must go then ...

Remember there's more to Barcelona than walking along Las Ramblas.

Alternatively ...

Why not head to Valencia for a less hectic break, with food and culture to rival the best of Barcelona.

3. Dubrovnik, Croatia

Dubrovnik plans to impose a 4,000 visitors a day cap to reduce tourist numbers. ELVIS BARUKCIC/AFP/AFP/Getty Images

With UNESCO threatening to take away its World Heritage status due to extreme overcrowding, Dubrovnik has decided to take drastic measures in order to cut tourist numbers.

The city is capping the number of people who can scale its 15th century ramparts at 4,000 a day -- 10,388 did so in one day alone bay in August 2016, many drawn by the city's starring role in "Game of Thrones."

The mayor is also planning on cutting the number of cruise ships entering the ancient port. Nearly 800,000 people disembarked from cruise liners in 2016, most staying for just three hours.

If you must go then ...

Travel independently and spend freely at local businesses that often miss out on money from those on cruises.

Alternatively ...

Stay in nearby Cavtat, which has a picturesque old town and empty beaches, perfect for escaping the crowds.

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4. Venice, Italy

Mass tourism in Venice has driven many residents away from the canal city. Miguel Medina/AFP/Getty Images

Sick of selfie stick-wielding tourists on the Rialto Bridge and cruise ships plying the Giudecca canal and back, Venetians took to the streets in 2017 to vent their frustration.

The city's population has plummeted to just 55,000 in response to mass tourism, which sees around 30 million people travel there each year.

In fact, there are now plans to prevent cruise liners sailing up the Giudecca canal, instead forcing them to take a new, longer route into the iconic lagoon.

If you must go then ...

Put down the selfie stick and try to explore quiet back waters. Also, try to dine in local restaurants and bars rather than the major tourist hotspots.

Alternatively ...

Annecy in France is home to a network of canals, a gorgeous lake and stunning architecture, all without the inescapable, overbearing crowds of Venice.

5. Santorini, Greece

Santorini welcomed around two million tourists in 2017. Courtesy Maggie Meng/Creative Commons/Flickr

There are few places in the world with sunset views as spectacular as Santorini, but the tiny island in the Greek Cyclades is reaching breaking point.

Almost two million people visited in 2017, 850,000 on cruise ships which drop anchor in its caldera, with passengers staying for a matter of hours rather than days.

While those numbers have been capped to 8,000 a day by the island's mayor, with a rising population due to the tourist boom, Santorini is in serious danger of losing its charm.

If you must go then ...

Stay at a local B&B and avoid the ethically dubious donkey rides which take tourists up and down to the harbor.

Alternatively ...

Naxos is within the same group of islands as Santorini, with rugged hills and beautiful beaches. Patmos, in the Dodecanese, is also a worthy, peaceful alternative, with excellent beaches and restaurants.

6. Bhutan

Bhutan has been attempting to minimize the impact of tourism by charging travelers a daily fee. Bhutan Tourism

Although it operates a "high value, low impact" tourism policy and charges visitors $200 or $250 per day depending on the time of year (with a $40 surcharge for groups of two or single travelers), there are increasing worries about how tourism is affecting the tiny Himalayan kingdom of Bhutan.

Locals have cited concerns about the environmental impact on its fragile ecosystem, as well as an over reliance on foreign visitors.

If you must go then ...

Be respectful of the country's Buddhist traditions and avoid leaving any litter behind.

Alternatively ...

The neighboring Indian state of Arunachal Pradesh has ancient Buddhist monasteries and stunning mountains to explore, without the same hefty daily fee.

7. Taj Mahal, India

India is limiting the amount of domestic visitors to the Taj Mahal. Dominique Faget /AFP/Getty Images

A colossal eight million tourists visit the Taj Mahal each year, with international visitor making up around half. The result is a chaotic experience, with crowds jostling to get into the grounds of the world's most iconic mausoleum.

But with the white marble yellowing and pollution rife in the adjacent Yamuna river, plans are afoot to curb numbers.

Authorities are considering limiting the amount of 40 rupee (around 60 cents) discounted fee tickets currently being offered to domestic visitors to 40,000 a day.

However international tourists, who are charged a far steeper 1,000 rupees ($15), will still be able to come in their droves.

If you must go then ...

Arrive at dawn. Gates open at 6 a.m., and it's best to be there by then. Also, be prepared to be jostled.

Alternatively ...

The Humayun tomb in Delhi may not be as spectacular, but the crowds here are nowhere near as relentless as those at the Taj.

8. Mount Everest, Nepal-side

Nepal has amended its mountaineering regulatiions, SHERING SHERPA/AFP/Getty Images

Local sherpas have long complained that a boom in numbers is causing dangerous overcrowding on the world's highest mountain above sea level.

Having already limited permits in 2015 to climbers with experience of high peaks, Nepal has now gone one step further, controversially banning blind people, double amputees (with the exception of those who obtain medical certificates) and solo climbers (unless accompanied by a guide) from attempting to conquer Everest or any other mountains in the central Himalayan country.

Officials say the new guidelines have been implemented to reduce accidents and climbing-related deaths.

If you must go then ...

Make sure you have plenty of climbing experience, as well an abundance of cash. Permits to climb Everest from Nepal cost $11,000.

Alternatively ...

Why not climb Lhotse Middle instead? The fourth highest mountain in the world lies south of Everest and has only been open to visitors since 2013.

9.Machu Picchu, Peru

The Inca citadel of Machu Picchu is Peru's most-visited site. EITAN ABRAMOVICH/AFP/AFP/Getty Images

Some 5,000 people a day visited Machu Picchu in 2016, double the number recommended by UNESCO.

Despite foreign travelers requiring an official guide since 2014, Peru's government stepped in to issue new timed visiting slots in July 2017, with a morning session from 6 a.m. until midday and an afternoon session from noon until 5.30 p.m.

While the restrictions aim to stop overcrowding, the effects are yet to be seen.

If you must go then ...

Visit between October and April. Although this is rainy season, the number of visitors will be lower and you'll have the chance of seeing the citadel minus the crowds.

Alternatively ...

Increasingly safe and less burdened by tourism than Peru, Colombia is home to the spectacular Lost City. Far fewer tourists come here, making it easier to explore.

10. Galápagos Islands, Ecuador

The Galápagos Islands have tightened travel regulations in a bid to preserve the natural habitat. RODRIGO BUENDIA/AFP/Getty Images

Protecting arguably the most famous natural habitat in the world is a tough task for the Ecuadorian government, with visitors to the Galápagos Islands limited to specific sites and marked trails only and a guide required at all times.

However new rules were introduced last year to help to keep the Ecuadorian province in pristine condition.

They stated that before entering, visitors must show a valid return airline ticket, have a reservation at a hotel or a letter from a resident inviting them to stay and a special transit control card. However, it's not yet clear when these new regulations will come into force.

If you must go then ...

Make sure to stick to the 14 rules outlined by the Galapagos National Park

Alternatively ...

Peru's Islas Ballestas, off the Pacific coast near Pisco, make for a memorable trip, with thousands of seabirds, penguins, sea lions and seals across the islands.

11. Cinque Terre, Italy

Authorities have discussed a possible tourist quota to combat overcrowding in Italy's Cinque Terre. Daniel Stockman/Flickr/CC by SA 2.0

The five vertiginous villages of Cinque Terre on the Italian Riviera drew a massive 2.5 million visitors in 2015, leading authorities to pledge a cap of 1.5 million tourists the following year.

While this statement was later rebuked and no limits have been put in to place, the concerns about mass tourism are real.

Cruise liners regularly bring in visitors who don't spend money in the area, while the huge swathes of tourists are said to have led to more landslides and rock falls.

If you must go then ...

Visit outside the summer season and go to local restaurants and businesses.

Alternatively ...

Head south to the gorgeous town of Portovenere. With no rail access, it is less enamored by tourists and is all the better for it.

12. Antarctica

Visitors to Antarctica have been on the rise in recent years. Eitan Abramovich/AFP/Getty Images

Often described as the last wilderness on Earth, environmentalists have long been concerned about the impact of tourists visiting Antarctica.

Today boats sailing around the southern continent aren't allowed to take more than 500 passengers, with many carrying as little as 100 due to strict rules on the amount of people that can arrive at any one time.

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While the southernmost continent has no permanent residents, visitor numbers have been steadily creeping up in recent years, with 44,367 tourists traveling there during the 2016/17 season.

The boom in numbers has raised concerns about the potential exploitation of the South Pole.

If you must go then ...

Join a science-led cruise with as few passengers on board as possible

Alternatively ...