San Blas is not your typical tourist destination but it has it's charms.

Borrego Beach   Borrego Beach is about 1/2 mile away and people either walk down there are take their bikes.  One of the nice things about the beaches is they have ramadas, which are palm covered restaurants where you can sit at a table in the shade and order drinks or food.  Many of them have hammocks where you can relax and read.  In most of the places, there is no pressure to buy - you can buy a coke for a dollar and spend the whole day, or you can order some nice fish or shrimp or guacamole.  This is the number one activity in San Blas. The most popular places with the gringos are Govinos, Stoners and Jacales. All the ramadas have food and the menus tend to be the same wherever you go - different recipes involving fish or shrimp. The beaches in San Blas are not crowded, especially during the week and as you walk down the beach yours will be the only footprints. If you walk down to the end of the beach there is an estuary with a beautiful tropical view.  We call it our ShangriLa.
Las Islitas  Las Islitas is about 5 miles outside of San Blas and no doubt one of the prettiest beaches I have ever been to (and I have been to a lot).   All the ramadas are nice, but my favorites are Mysis and the one right before it (called Las Islitas). They are both way down the end and are on the best swimming beach. If you want the perfect day, go out there and order the fish sarandeando, cooked over mangrove wood.   The only problem in this paradise is the bugs - this is jejene heaven, but they really haven't been that bad lately. They are at their worst late afternoon and during a full moon.  
Combis run close by Las Islitas about every half hour or you can take a taxi for about 100 pesos.  
Isla Del Rey   You have to take a boat across the estuary to get to Isla Del Rey  but the price is reasonable.  This beach is almost completely deserted and seems to go on forever.  You can climb up to the lighthouse to see a view of all of San Blas.  Isla del Rey is sacred ground for the Huichol Indians and they often perform there spiritual ceremonies there in their native costumes.
Jungle Boat Ride  You can take a boat ride through the mangrove swamps to a natural fresh water pool where you can swim with the crocodiles*.   For us, swimming with the dolphins is boring, boring, boring.   You will see many species of birds, crocodiles in the wild, turtles and iguanas.  You can also visit the crocodile farm as part of this excursion.  This trip is a must.
Crocodile Farm  The drive to the crocodile farm takes about 15 minutes from San Blas. You can take a dip in the fresh water spring natural pool as you listen to the sounds of the jungle. There are swimming ladders and the water is crystal clear, cool and deep. They feed the crocodiles on Fridays if you are into that type of thing. People tell me they don't want to go because they don't like animals in cages, but actually this place repopulates the crocodile population all over Mexxico. When I first came to San Blas in the 70s there weren't any crocodiles.
Entrance fee: 30 pesos.
Spanish Fort  You can walk up to the old Spanish fort and old church but the hill is rather steep so on a hot day I would suggest a taxi.  For some reason the church always reminds me of Raiders of the Lost Ark. There is a restaurnt up there and a small museum, and a panoramic view of the town (not to mention a great view of my house). The amazing thing about many of the attracions in San Blas is there are usually no people. The nearby cemetary is also interesting, espeically on Day of the Dead when they have music and food, while people repair and decorate the gravesites.
San Blas Plaza  San Blas is a very active town for its size. There are always people on the plaza and there are many events, mostly involving school children. On San Blas Day (Feb 3rd) they have fireworks right over the plaza. Very exciting. (Wear your running shoes). Once I went down there once in the summer and unannounced there was a Peruvian dance troup with about 20 dancers and 10 costume changes. I was lucky enough to be one of the 30 people watching it. There are stalls selling artesan crafts and Chinese goods. It is a nice place to relax and have an ice cream and watch the world go by. If you have children this is a good spot for them make friends with the locals.

Crocodile Overlook As you drive out of town about a mile past the bridge is the crocodile overlook. It is a beautiful view and you are almost sure to see crocodiles. Free parking.
Hiking  There are many beautiful places to hike around San Blas.  You can hike for miles along the beaches. Or, you can take a bus and go hiking up at La Bajada along the Camino Real through the coffee plantations. 

Matanchen Beach
The Pier (El Muelle de San Blas?)
The pier is located right in front of the entrance to the new expressway to Tepic. It is a nice walk with a good view of the mountains and the coastline. Usually I don't like crowds but a trip to the pier on Sundays would be fun to mix with the locals and their families. El Chaco
El Chaco is located right before you get to Aticama Hill. They have a large pool, with comfortable lounge chairs and umbrellas, surrounded by hundreds of coco palms. I like it best in the mornings when it is quiet. They also have a ramada on the nearby swimming beach, a hotel, restaurant and trailer hookups. Entrance fee is about 50 pesos, less for locals.
Etc. Beach Club  This is a new place located on Matanchen Beach.  It is a large attractive restaurant with a swimming pool on a quiet area of a long, wide beach.  From what I could tell, the food seems quite good and it is also a nice place to relax and spend the day.  If you like peace and quiet, go during the week.   Take the El Llano bus and look for the sign. Only open on weekends.
Sunday Market
The Sunday Market takes place in the Aticama Cultural center on Sunday mornings from November thru the end of April. Local vendors sell jewelry, hammocks, huichol bags, and other artisan goods. You can chow down on chile rellenos, empanadas, fresh brewed local coffee and other delicious homemade treats.
Aticama Museum A surpising number of local artifacts from Aticama, Los Cocos, Santa Cruz and San Blas can be found at the Atricama Musea
Los Cocos
Casa Maņana  Casa Maņana is a hotel and restaurant located on the beach in Los Cocos.  You can spend the afternoon here, have a nice lunch, use the pool, or take a walk on the beach or on the hills above the beach.  On Saturdays they serve delicious pizza. On Sundays there is a breakfast buffet (pronounced Buffett as in Jimmy Buffett). Everybody loves Casa Maņana and there's no bugs!! 

*Not responsible for any damages that might occur.