Citizens of the following countries do not need a visa to visit Canada for a stay of (generally) up to six months, provided no work is undertaken and the traveller holds a passport valid for six months beyond their intended date of departure:
Andorra, Anguilla, Antigua and Barbuda, Australia, Austria, Bahamas, Barbados, Belgium, Bermuda, Botswana, British Virgin Islands, Brunei, Cayman Islands, Croatia, Cyprus, Denmark, Estonia, Falkland Islands, Finland, France, Germany, Gibraltar, Greece, Holy See, Hong Kong (BNO Passport or SAR Passport), Hungary, Iceland, Ireland, Israel (National Passport holders only), Italy, Japan, Latvia, Lithuania (biometric passports only), Liechtenstein, Luxembourg, Malta, Monaco, Montserrat, Namibia, Netherlands, New Zealand, Norway, Papua New Guinea, Pitcairn Islands, Poland (biometric passports only), Portugal, Saint Kitts and Nevis, St. Lucia, Saint Vincent and the Grenadines, San Marino, Singapore, Slovakia, Solomon Islands, South Korea, Spain, St. Helena, Swaziland, Sweden, Slovenia, Switzerland, Taiwan (must be ordinary passport including personal identification number), Turks and Caicos Islands, United Kingdom (including British (Overseas) Citizens that are re-admissible to the United Kingdom), United States, and Western Samoa.
A visa exemption also applies to individuals holding nationalities that are not specified above if they are in possession of a US Green Card or can provide other evidence of permanent residence in the United States. Persons who do not require a visa and who are entering for any reason other than tourism must have a letter of invitation from the individual, business, or organization that they are visiting. (See  for information about letters of invitation and what information they need to contain).
All others will be required to obtain a Temporary Resident Visa to enter the country. This can be done at the applicants' nearest Canadian Visa Office. Applicants are required to submit, as part of their application:
-A valid travel document (such as a passport)
-Two properly-formatted, passport-sized photos for all applicants
-The application fee (The fee per person is $75 for a single entry visa, $150 for a multiple entry visa or $400 for a family (multiple or single entry)
-Reservation confirmation (for tourists) or letter of invitation (for everybody else).
-Proof that you have enough money for your visit to Canada. The amount of money may vary, depending on the circumstances for your visit, how long you will stay and whether you will stay in a hotel, or with friends or relatives. You can get more information from the visa office.
-Other documents as required. These documents could be identification cards, proof of employment, or a proposed itinerary. Check the website of the visa office responsible for the country or region where you live for more information.
If you plan to visit the United States and do not travel outside the borders of the US, you can use your single entry visa to re-enter as long as the visa has not passed its expiry date.
All potential visitors, whether applying for a temporary resident visa or requesting landing permission at the border must be of good moral character, and under Canadian law this means having a completely clean criminal history. Immigration authorities take character concerns of visitors very seriously and any offence, misdemeanor or felony, regardless of how minor or how long ago it took place can exclude you from Canada for a period of time, indefinitely, or permanently. In fact, even former U.S. President George W. Bush needed to apply for a waiver to enter on an official state visit during his term in office because of a past D.U.I. There are a few exceptions, and if you are inadmissible because of a criminal conviction, you do have some options.
As a general rule, a conviction for anything more serious than a speeding ticket will keep you out of Canada for at least five years from the date you finish your sentence. More serious offences (such as felonies) may require you to wait up to ten years, or in the most serious cases obtain a pardon or other civil relief locally before applying for entry. In addition to criminal convictions, certain "summary offences" (which include minor drug possession tickets that are not handled through the criminal system) are considered criminal convictions for the purpose of immigration law, even if you were never arrested, charged with a crime or sentenced. Additionally, you cannot enter Canada if there are current charges pending against you or a trial is underway.
Although unlikely as a visitor who meets all other entry requirements, you may also be refused if you have significant unpaid debt, have an active civil judgement against you, or have recently declared bankruptcy. In these cases, you can regain your ability to enter Canada by either paying the debt in full, showing evidence of a payment plan in good standing or after a bankruptcy showing a history of financial solvency over the period of a few years.
Offences committed before the age of 18, parking tickets, local ordinance violations and crimes of conscience (such as publishing statements critical of the government in China) generally do not result in inadmissibility. Similarly, non-criminal traffic tickets usually do not result in inadmissibility, although if you were ever required to appear in court over a traffic violation (not simply going to court to challenge a ticket) or you accumulated enough points that your license was summarily suspended or revoked, you may be inadmissible and should contact a Canadian embassy or high counsel for advice.
From the United States
If you are travelling to Canada from the United States and you are not a permanent resident of either country you need to be careful to satisfy the U.S. authorities on any subsequent trip that you have not exceeded their limits on stays in North America. Your time in Canada counts towards your maximum allowed United States stay if you are returning to the U.S. prior to your departure from North America.
-If you are returning to the U.S. in this trip, keep your visa documents. Do not hand over your US visa or visa waiver card (I-94 or I-94W) to border control. You can enter the U.S. multiple times during the time allocated to your visa (for Western tourists, normally 90 days), but you need to have the immigration document as well to validate the visa. If you come back from the U.S. without that document, you will not only have to apply again for a visa or visa waiver but also will also need to satisfy U.S. immigration of the validity of your trip (meaning to show them that you will not intend on immigrating there).
-If your default U.S. time is going to run out while you are in Canada, and you want to return to the US direct from Canada, you need to apply for a U.S. visa with a longer time period (eg B-1/B-2, or a C-1 transit visa) before your first trip through the U.S.. For example, if you are going to stay in Canada for six months, and you transit through the US on a visa waiver, then the U.S. will regard your six months in Canada as not allowing you to return to the U.S. without leaving North America first, as you have stayed more than 90 days in North America in total. Note that in this scenario, you have not done anything wrong by visiting the U.S. and then staying in Canada for a long time, simply that the U.S. will not allow you to return directly from Canada, you have to reset their clock by leaving North America. Visa waiver travelers may be able to avoid this by returning their I-94W (green) form to their airline upon departing the U.S., or to the Canadian immigration inspector if entering Canada by land; since the U.S. has no outbound immigration check, it's up to the traveler to remember this.
-If you are intending to leave North America entirely without returning to the U.S. on this trip, return any visa documents at the time of leaving the U.S. for Canada. This means handing over your I-94 or I-94W card to airline staff at the check-in counter if departing by air, or to the Canadian immigration inspector if departing by land. If you do not, you will need to prove to the U.S. that you didn't overstay to be admitted on future trips (the US CBP website has information on how to correct this mistake).
You are likely to arrive to Canada by air, most likely into Montreal, Ottawa, Toronto, Calgary or Vancouver (the 5 largest cities, from East to West). Many other cities have international airports as well, with the following being of particular use to visitors: Halifax, St. John's, Winnipeg, Edmonton, Regina, Saskatoon, Kelowna, and Victoria.
Air Canada and WestJet are the country's only national air carriers, covering the entire country and international destinations (Note that a number of regional domestic airlines also exist as well as charter airlines serving only international destinations).
As a rule of thumb, all Canadian three-letter IATA airport codes start with a "Y".
Luggage allowance for flights to or from Canada usually operates on a piece-wise in addition to the weight system even for foreign carriers. This means that you are allowed a limited number of bags to check-in where each bag should not exceed certain linear dimensions (computed by adding the length, width and height of the bags). The exact restrictions on weight, linear dimension and number of baggage allowed are determined by the carrier you are flying with and the class of service you are travelling in, usually individual bags may be up to 23 kilos (50 lb) if traveling in economy class.
Additionally, if you are coming from the United States, be advised that Air Canada (on transborder itineraries only - not Canadian domestic service) as well as all US based carriers that operate transborder service (Alaska, American, Delta, United and US Airways) charge checked bag fees. Typically $25 for a single bag of up to 23 kilos/ 50 pounds, and $35-50 for a second bag, unless you qualify for a fee waiver based on elite status or class of service.
You might also enter the country by road from the United States through one of several border crossing points. Obviously, the same rules will apply here, but if your case is not straightforward, expect to be delayed, as the officials here (especially in more rural areas) see fewer international travelers than at the airports. Also expect delays during holiday periods, as border crossings can become clogged with traffic.
Drivers of American cars will need a Canadian Non-Resident Insurance Certificate in addition to your standard insurance card. Canada has some of the highest auto insurance minimums in the world $200,000 in all provinces except Quebec and Nova Scotia (which are $50,000 and $500,000 respectively.) Since most US states have insurance minimums under $50,000 and some states do not require insurance at all, the non-resident certificate signifies that your insurance company will cover you up to the mandatory limits while driving in Canada. Rules regarding the issuing of this certificate vary widely depending on which carrier you have. GEICO and AAA will issue a certificate valid for the entire term of your policy if you ask for it. Liberty Mutual and Progressive will only issue a certificate with advance approval for a specific date range, and some insurance companies (especially smaller local insurance companies in non-border states) will not cover you in Canada at all. If you are planning on driving into Canada, its very important to talk to your insurance company as soon as you know you'll be going.
If you are a U.S. Citizen or permanent resident and travel to Canada frequently, you may consider applying for a NEXUS card. NEXUS allows pre-approved, low risk travelers to use expedited inspection lanes both into Canada and the United States at many land crossings with minimal questioning. You can also utilize kiosks to make your customs declaration and clear the border at major international airports if you opt for an iris scan. The application fee is $50 and requires being legally admissible to both nations, thorough background investigation, fingerprinting and an interview with both U.S. Customs and Border Protection and Canada Border Services Agency.
If you are driving a U.S. car, chances are your speedometer is in miles per hour. If you intend to enter Canada using a U.S. car, take note that after crossing the border going north, the road signs change into metric units (i.e. distances are in kilometres, speed limits posted are in kilometres per hour). As the usual speed limit in the U.S. on freeways is around 50-60 miles/hour, you will read a higher number for the speed limit (in km/hour) once past the border, ie. 100 km/h = 62 mp/h. One mile is equivalent to 1.6 km so divide what you see on the road signs by 1.6 to get its equivalent in miles ie. 40km = 25 miles.
When driving within Montreal, Vancouver or Toronto keep in mind that these cities are densely populated and parking can be difficult to find and/or expensive. All three cities provide extensive public transit, so it is easy to park in a central location, or at your hotel or lodging, and still travel in the metropolitan area. You can usually obtain maps of the public transit systems at airports, subway kiosks and train stations.
Via Rail (http://www.viarail.ca/
) is Canada's national passenger rail service. Amtrak (http://www.amtrak.com/
) provides connecting rail service to Toronto from New York via Niagara Falls, Montreal from New York and Vancouver from Seattle via Bellingham. The train is an inexpensive way to get into Canada, with tickets starting from as low as US$43 return to Vancouver. There is also thruway service between Seattle and Vancouver.
Be wary though: Not many private citizens in Canada take the train as a regular means of transportation. Most citizens simply drive to where they want to go if the distance is short (which in Canada can still mean hundreds of kilometres!), or fly if the distance is long.
Important: If you're traveling cross-border on Amtrak service, you must have your tickets validated prior to boarding. Pick up your tickets from the window (not the Quick-Trak kiosk) and show your passport or travel document to the agent (your travel document information is sent ahead of time on a manifest to border services to facilitate crossing procedures). Some stations, such as New York City have a dedicated window for international passengers.
Greyhound Canada (http://www.greyhound.ca/
) serves many destinations in Canada, with connecting service to regional lines and U.S. Greyhound coaches. Be sure to inquire about discounts and travel packages that allow for frequent stops as you travel across Canada. Many routes connect major Canadian and American cities including Montreal - New York City which is operated by New York Trailways, Vancouver - Seattle operated by Greyhound and Toronto - New York City via Buffalo, this route in particular is operated by a number of bus companies: Greyhound, Coach Canada, New York Trailways and two new discount services: Megabus and Ne-On.
In British Columbia, you can enter Canada by ferry from Alaska and Washington. Alaska Marine Highway serves Prince Rupert, whereas Washington State Ferries serves Sidney (near Victoria) through the San Juan islands. There is a car ferry from Victoria to Port Angeles run by Black Ball; there are also tourist-oriented passenger-only ferries running from Victoria to points in Washington.
There is a passenger ferry running from Fortune in Newfoundland to Saint Pierre and Miquelon.
A small car ferry operates between Wolfe Island, Ontario (near Kingston) and Cape Vincent, NY.
A small car ferry operates between Pelee Island Ontario, Kingsville Ontario and Sandusky Ohio when ice and weather allows.
The CAT car ferry between Rochester, NY and Toronto, Ontario was discontinued in January 2006 because of poor ridership. The Bay Ferries route from Bar Harbor in Maine to Yarmouth, Nova Scotia, also called the CAT, was discontinued in 2010 due to a lack of funding. (Bay Ferries does still run a New Brunswick to Nova Scotia ferry.)
Several cruise lines run cruises between the eastern United States and Halifax. Most freight routes run to Montreal on the east coast and Vancouver on the west coast. International passengers will be required to pass through customs in their port of arrival.