You might think summer is the best time to travel to the Mediterranean because most ships are in Europe. Other times of year are better.

There's never a time when you can't go on a cruise ship in the Med. During the peak season, you will find the most ships and itinerary choices, while the lowest during the off season. The shoulder season is when the Mediterranean cruise season begins or ends.

The shoulder season is when I think the best time to cruise the Mediterranean is. I think April is my favorite month. Let's take a look at the variables to determine the best time for you to head to the region and hop on a cruise ship.

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Introduction to Mediterranean geography

Turkey's Aegean coast. (Photo by Anton Petrus/Getty Images)

There are 11 small seas in the Mediterranean Sea. Some cruise lines like to label their itineraries according to the smaller sea names, making it difficult to shop for Mediterranean cruises.

There are cruises to the Adriatic between Italy's east coast and the central European countries of Yugoslavia, Croatia, Montenegro and Albania. The cruises traverse the large open sea between Greece and Turkey and go as far south as Crete and as far north as Istanbul. You can sail through the Ionian Sea to Sicily and the Greek island of Corfu.

Mediterranean includes Monaco, the southern coast of France and Spain, and even Israel. Mediterranean cruises include ports in Portugal. Portugal is considered part of the Mediterranean region despite not having a coastline on the Mediterranean Sea.

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The best time to cruise the Mediterranean based on choices of ships and itineraries

View of the city of Positano on Italy's Amalfi Coast. (Photo by Kirk Fisher/Getty Images)

The region has a number of cruise lines that sail throughout the year. It's possible to cruise the Mediterranean in winter, but you can't choose your ports. There were no sailings to the popular ports in December or January.

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The majority of the winter offerings go to the western ports of Italy and France. Istanbul, western Turkey, Israel and even Alexandria, Egypt are some of the destinations that can be sailed from Athens. Only Costa and Viking offer cruises that include Venice in the winter. Spanish and Portuguese destinations are the focus of Norwegian's winter Mediterranean itineraries.

There are more ships in the spring and early summer. We found a lot of ships that were going to visit Venice, Corfu and Santorini. There are many ships ready to sail to the Med in March. The list of mainstream, premium and luxury lines cruising Mediterranean waters grows larger in April.

The choices of cruise lines and itineraries are at their peak in June. Carnival Cruise Line decided to sail a short season of 10 and 11 night cruises in September and October instead of in June.

The majority of ships stay in Europe during the summer months. Disney Cruise Line leaves the Mediterranean in July. Celebrity is one of the last to leave and continues its Mediterranean cruises into December and January.

You can rule out winter if you want to see Venice or Santorini, but there are plenty of options between March and October. The number of ships calling at Mediterranean ports has fallen by the end of the month.

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The best time for a Mediterranean sailing based on prices and crowds

The winter is a good time to go on a Mediterranean cruise. Most travelers prefer a little more warmth and a bigger choice of ports, but still prioritize a good price and lighter crowds.

Mediterranean cruise fares peak in the summer months. Between the spring and summer, the prices for big-ship cruises ranged from $60 per person per night in the spring to $90 per person per night in the summer. The spring fares on Silversea were hundreds of dollars cheaper than the summer fares. Spring break travel causes rates to go up in March. The best deals were found in the spring and fall.

We looked at two popular ports where the effect of multiple ships is felt the most -- Santorini and Venice. If you go to Santorini in June or July, you'll find yourself fighting for space with as many as 15,000 other passengers.

There is an April or November stop where the daily cruise passenger load is around 3000. There were days in April when only a few mid-sized ships were scheduled to dock.

A crowded Santorini. (Photo by George Pachantouris/Getty Images)

When four mid-sized ships arrived in Santorini, it was difficult to walk through the narrow maze of shops, restaurants and hotels. I was worried about returning to the ship on time because the lines at the cable car were so long. I don't know how you would be able to walk through town with so many people in the port. The narrow rim of the cliffs is where most of the things that tourists want to see are located.

Venice has recently cut back on its cruise tourism capacity in part by forcing some ships to dock in alternate ports and bringing guests to the city by bus. In June there were as many as 6,000 passengers arriving, but as few as 4,000. In the month of April, cruise passenger arrivals are usually below 3000 per day. Venice has a much more complex crowd control scenario than Santorini.

If you want to avoid high prices and crowd congestion, you need to stick with the shoulder seasons of spring and fall.

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The best time to cruise the Med based on weather

Even Istanbul can be chilly with an average high temperature of 48 degrees in the month of January. In December and January, temperatures in Athens, Rome, Barcelona, and most of the Greek islands are in the mid-50s.

In the larger cities, summer temperatures can get very hot. In July and August, the temperature in Athens goes up to 90 degrees. In the summer, Rome and Barcelona have cooler temperatures.

The Mediterranean has more rain in October and November than most other months, but the average monthly rain in the fall is three inches. Most of the Med sees less rain than the northern ports. You can walk through St. Mark's Square in rubber boots if you want. When booking a cruise on a ship that stops in Venice in November and December, be aware that the high tides are most likely to occur in November and December.

If the Mediterranean cruise is going to happen in January, February and December because of the cold, July and August because of the heat, and October, November and December because of the rain, you shouldn't book it in those months. March, April, May, June and September are the best months to cruise in the Mediterranean.

Is it a good time to book a cruise?

Bottom line

There are different reasons for the timing of a cruise. Traveling while school is not in session or maximizing time at the beach are possibilities. Maybe you are loyal to a particular cruise line and want to go on a new ship?

There is a good time to travel to the Mediterranean. April is my favorite because of the confluence of reasonable fares, pleasant weather, manageable crowds and an abundance of itinerary and ship choices.

If I'm right, shoulder-season months are the best time to cruise the Mediterranean, but I want you and your travel partners to go when it's best for you. Even with less than ideal weather, a dream cruise in Europe is better than no cruise at all.

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