Like the rest of western Washington, San Juan Islands are best visited during the summer, when the sun shines up to 18 hours a day with barely any rain. Expect cooler weather compared to the mainland as the surrounding seas cools the warm air. Average summertime temperatures are around 60 °F (16 °C).

in winter, the seas makes the islands a touch milder than the mainland. The islands sometimes get lucky and stay dry while the mainland is soaked, thanks to the Olympic Mountains in the south that block the precipitation. The bigger issue is the wind, which can howl and cause problems in areas exposed to the water. These typically come after a rainstorm or ahead of dry and chilly weather.

About 75 rocks, reefs, parks and other sites across the region are protected in the San Juan Islands National Monument, established in 2013. The National Monument includes archaeological sites of the Coast Salish peoples, lighthouses and relics of early European American settlers, and the biodiversity of island life.

The monument has no central hub for visitors. Almost all of its parcels are small, and many are not meant to be accessed, but many others are described in listings across the various island guides.

The San Juan Islands are one of the most popular areas for cruising on small craft in North America. Most towns are built around their harbors and offer a variety of services, restaurants, and hotels within walking distance of marinas. Even the less populated islands often have a public dock or public buoys for visiting boaters, check individual island and city listings for specifics.

Water Taxi services can transport to the small islands such as Blakely, Decatur and Henry Islands.

If interested in cruising to the islands, there are charter companies in both Anacortes and Bellingham. The Waggoner Cruising Guide is a great resource for these waters.

• Kenmore Air, toll-free: +1-866-435-9524, fax: +1-425-485-4774, [email protected]. Kenmore Air seaplanes make several flights daily from downtown Seattle's Lake Union to six locations in the San Juan Islands with two on San Juan Island, three on Orcas Island, and one destination on Lopez Island. Kenmore Air Express also offers daily land plane service between Seattle's Boeing Field/King County International Airport (BFI ^IATA) and Friday Harbor Airport (FRD ^IATA). Complimentary shuttle transfers are available to/from Seattle-Tacoma International Airport (SEA ^IATA) for passengers on either Kenmore Air service. A quick and spectacular, though not cheap, way to arrive. $75-139. 
• Northwest Seaplanes, 860 W. Perimeter Road, Renton, toll-free: +1-800-690-0086. Scheduled and charter seaplane flights to destinations from South Lake Washington, in the heart of Seattle to the San Juan Islands, Vancouver Island, and British Columbia’s Inside Passage. They operate 4 planes each offering six seats. 

Bringing a car on the ferry is the best option for exploring the remote areas of the main islands. If you can't, car rentals are available from Friday Harbor, Orcas Village and Eastsound.

Smaller islands generally have unimproved county roads. Due to their remote locations and lack of ferry service these roads often serve as foot trails, and you are more likely to see someone traveling by horse than car.

The four largest Islands (Orcas, San Juan, Lopez, and Shaw) are connected by Washington State Ferries.

The San Juan Islands are the most popular sailing charter area in the Pacific Northwest and one of the most popular destinations for cruising on small craft in the United States. Small towns and harbors are geared towards visiting boaters and many of the areas most scenic and remote areas can only be reached by boat. The area waters are reasonably protected even in storms off the Pacific, but due to the many underwater hazards some boating experience is helpful.

Many charter companies include a day of training in the charter package. See Waggoner Cruising Guide for more detailed navigational and recreational information.

The winding paved roads of the main islands are ideal for exploring by bike and bike rentals are available near many areas in the San Juan Islands. However, the smaller more remote islands often do not have paved roads, making traveling by bike more of a challenge.

Bicyclists have priority boarding on Washington State Ferries, so bikes can bypass the sometimes ridiculously long car lines and walk right onto the ferries.

Exploring on foot is perhaps the most rewarding way to view the islands. Many trails dot the various islands and state parks giving travelers an insightful view of their surroundings. Outside of the four main islands cars are more of an impractical luxury item rather than a means of transport. Many of the dirt roads see far more foot traffic than car traffic and basically serve as wide foot trails.

The San Juans are touted as the best place in the world to see orcas (killer whales). The Southern Resident Orcas live in the Salish Sea year-round. The spring season is when they are easiest to see in the San Juans.

There are other whales in these waters. Gray whales migrate through the islands, usually around April. Humpback whales also migrate through in the spring and summer.

There are large number of tour operators, departing from Friday Harbor, Roche Harbor, and larger cities on the mainland (such as Bellingham and Anacortes). The Whale Museum in Friday Harbor is a great resource for planning your own excursion.

Even if you miss out on seeing one of the bigger residents, you are almost certain to see harbor seals, otters, sea lions, and porpoises.

The San Juan Islands are in the Pacific Flyway, which extends from Alaska to South America. Almost 300 species of birds have been observed on the islands. The islands offer a variety of habitats for birds in a relatively compact area, from rocky sea shores to lush wetlands. The San Juan Islands Audubon Society holds regular meetings, bird counts and postings of bird activity. Bald Eagles, Great Blue Heron, Kingfishers and Cormorants are all common sights on the islands but rare birds are sometimes seen migrating through the area.

Check recent bird sightings at eBird's listing for San Juan County.

Sport crab fishing is popular here. Most fishermen look for the elusive and meaty Dungeness Crab, but other less popular crabs are plentiful. A wide array of crab traps are available from area sporting goods and marine stores. The red and white buoys marking the traps are a common sight on the water during the short crabbing season.

Crab season starts with a two-day opener July 1st and 2nd and follows up with crabbing every Thursday through Monday through Labor Day weekend. Fishing permits are required and can be purchased from a variety of local stores, more information is available from the Washington Department of Fish and Wildlife.

Sea kayaking allows the paddler a closer and slower look at their surroundings. The San Juans are littered with pristine forested parks and sheltered passages to secluded beaches. Or just explore the San Juan Islands many harbor towns that cater to kayakers with shops and restaurants accessible from the water.

Some camping areas in the various state parks in the area are only open to people powered vessels.

The cool, clean waters provide some of the finest shellfish habitat in the world. Washington State is the nation’s leading producer of farmed bivalve shellfish (clams, geoduck, mussels and oysters).

The San Juan Islands have dozens of Public Clam and Oyster Beaches. Maps of public shellfishing areas and health warnings and updates can be found online at the Washington Department of Fish and Wildlife. Permits are required and can be purchased online or in some sporting goods stores.

Keep wildlife wild. Though many of the animals in the Puget Sound area are used to seeing humans, they should not be fed or disturbed.

U.S. regulations require that boaters stay 200 yd (180 m) away from whales and keep the path of the whales clear.

Don't disturb resting seal pups. NOAA recommends at least a 100 yd (91 m) buffer around seals. Keep children and dogs away and report to the local stranding hotline. Report harassment or sightings of injured/stranded marine mammals by calling the NOAA Fisheries hotline at ☏ +1-800-853-1964. Seal pups 'haul out' to get much needed rest when they are young and are often alone for many hours. They are extremely vulnerable at this time and should be left alone. Only about 50% of Puget Sound seal pups make it through their first year so please help to protect their health.

Many visitors are surprised by their phone bill after returning from the San Juan Islands. Due to their proximity to Canada it is possible to get a better signal from a Canadian cell phone provider and, depending on your phone's settings, could add foreign roaming charges to your bill. Roche Harbor and north San Juan Island are notorious for having better Canadian service.

Many of the islands are remote enough that cell phones simply won't work, so don't plan on being dependent on them, especially in the outer islands.