Balboa Park

Balboa Park is a beautiful place to go for a stroll, people watch, and savor beautiful gardens and architecture. There are also many museums to check out. The colorful, central pedestrian square (Plaza de Panama) with its bright umbrellas and fountain is the center of the park . This area is gorgeous at night. Marvel at the lavish architecture in Balboa Park, which was built for the Panama-California Exposition in 1915.

The Museum of Us (Anthropology) has a Spanish tower with Mexican colors and tiles, called California Tower, that stretches to the blue sky. It has three tiers, from the bottom: quadrangle, octagon, then round. In the tower is a carillon that sounds every fifteen minutes with the Westminster Chimes. A musician plays three songs on the carillon every day at noon. You can tour the California Tower daily at 10:30, 12:30, 2:30, and 4:30 (tours last 40 minutes, and only six people go. Cost is the Museum of Us entrance fee of $20, plus $10 for the tower tour). It's wonderful to just walk by the California Tower, on El Prado, especially at sunset. The tower also has a glorious blue and gold dome, built to resemble a church in Taxco, Mexico. Its transcription, in Latin, speaks of a land of oil and honey, where wheat, barley, wines, and trees such as fig, pomegranate, and olive grow. The Museum of Us has interactive exhibits for kids such as one where you walk through a child's bedroom, forest, cave and ocean, and learn about yeti, kraken, unicorns and dragons, plus an exhibit about ancient Egypt.
Also in the central square is the Mingei International Museum in a delightful building called the House of Charm. Check out its Spanish bell towers and adorable pointed round extensions with small circular windows. It was built to resemble the Sanctuary of Guadalupe in Guadalajara, Mexico! Inside, the museum showcases folk art, craft and design. It has a large gift shop with interesting jewelry.  Behind is the Alcazar Garden, a walled garden with a star-shaped Spanish fountain and splendid flower beds that vary each season. Do not miss it in spring!
Across from the House of Charm is the House of Hospitality. Walk into the tropical courtyard and admire the fountain with a sculpture of an Indian woman with pottery. Near the benches check out the wooden multi-colored carved decorations reminiscent of an abacus. Here you can grab a cup of coffee from the refreshment stand called Prado Perk and also pop into the Visitor Center.
The Casa de Balboa contains the Museum of Photographic Arts and San Diego Model Railroad Museum, plus a cafe in its dark entrance hall called Cafe in the Park. 
The Botanical Building fronted by a long reflection pond with ducks is a favorite with kids. There are tall wildflowers in front of it, making for a nice photo spot.  
The Bea Everson fountain is a more sterile-looking water feature, a large pale blue pool with fountain in an expansive cement open space. Some homeless people hang out here. It is next to the modern-looking glass Natural History Museum.
Musicians often play on weekends under the huge moreton bay fig tree south of Spanish Village, or in the long, bustling, pedestrian-only street called El Prado, in front of Casa de Balboa. Food stands line this stretch of El Prado too. Musicians, such as a string quartet, also play by the Botanical Building, and a flamenco guitarist plays by the cafe at Mingei International Museum.
You can also watch a free concert at the Spreckels Organ Pavilion, a spectacularly beautiful semi-circular outdoor pavilion built in Italian-Renaissance style. Organ concerts are every Sunday at 2pm, and summer concerts are Mondays 7:30pm from late June to Labor Day. Some Sundays at 2pm they have a family show (see their website), and other nights they have operas. There is a nativity scene in the pavilion at Christmastime. The pavilion is lit up beautifully at night, as is much of the park. It is a little distracting during the concerts how airplanes fly over every five minutes, and a loud tram goes by, if you sit in the shady side wing.
Spanish Village is a gorgeous square with delightful colored clay tiles on the ground. Here you can buy a delicious smoothie from a stand, Daniel's Coffee, and also visit the San Diego Mineral and Gem Society for free, where you can buy some precious gems in the shape of spheres, moons, and stars. This was one of our favorite things to do at the park!
There are many other museums to visit- check their open times because on many days they are closed. The Comic-Con Museum has high ceilings and plenty of open space with benches where you can rest in the AC, making it appealing. It is interesting to see the exhibits of costumes from movies, comic books from days of old, and items from favorite shows. The San Diego Model Railroad Museum has fun models of the railways of various cities across the USA- it is the largest indoor model railway in the world. San Diego Air and Space Museum is packed with planes. Both of these museums are a little dusty and not interactive. At Fleet Science Center, kids can build their own inventions, and touch a tornado. San Diego Natural History Museum has a giant-screen theater, fossils, gems, taxidermy, and skeletons, and kids love it.
The San Diego Museum of Art (in the central pedestrian square) is a small museum with some good European art (especially religious art), and a counter-service patio cafe with good food, beside a lawn with modern-art sculptures. The Museum of Photographic Arts has works by Ansel Adams. Timken Art Museum has works by European masters, and a grassy lawn where people lay out and picnic.
There are many gardens to check out, all spectacular. The only one that is not free of charge is the Japanese Friendship Garden, where a zig zagging loop path takes you down into a valley and back. Here you see lovely trees, a stream, boulders, a waterfall, an arch, a pavilion, and spirit houses. You can line up to see cherry blossoms in March. In late spring and early summer check out the Rose Garden, packed with red, yellow, and all varieties of roses. It is high up overlooking a valley with nice cool breezes. A tiled fountain adds a water feature. Next to the Rose Garden is the Desert Garden, with cactus of all sorts, in amazing Dr. Suess-like shapes. There are some stunning African trees as well.  The Zoro Garden is a hidden, sunken garden with two huge ficus trees with amazing roots. The Palm Garden, in a canyon, has lovely hiking trails and incredible trees above you. Come when the sky is blue so that the palms look even more amazing. It was one of my favorite parts of Balboa Park. The Alcazar Garden, a formal garden with wonderful flower beds that vary by season, hedges, and Spanish bell tower views is a delight. 
For little kids there is the San Diego Zoo, the 1910 children's carousel, and the miniature railroad which opens at 11am. The carousel is well-maintained, offering a smooth and very fast horse ride! But the music is too distracting, almost like theme-park music. Kids will also enjoy Pepper Grove Playground, with lots of animals to climb, in the south portion of the park. A visit to Marie Hitchcock Puppet Theatre is a treat (Wed-Sun 11, 1, 2:30). 
There are some good places to eat a meal. The first is the coffee shop called Craft Cafe outside the Mingei International Museum. You can buy lunch at the counter inside and eat it outside beside the archways. Kids love the chicken nuggets and I loved the chicken bowl, plus Butterfly Flower Lemonade.
Another good place to eat is Panama 66, in a hidden courtyard to the left of the San Diego Museum of Art. To find it, look for its many arches. You order at a counter near the bar and they bring your food to your table. The Braised Beef is delicious!
The House of Hospitality has a little coffee stand called Prado Perk, in its courtyard entrance. And the Museum of Photographic Arts has a little cafe inside its dark entrance hallway, called Cafe in the Park. You can also get a Teriyaki Rice Bowl at the Tea Pavilion outside the Japanese Friendship Garden, and eat it on the picnic tables under red umbrellas. In the Spanish Village, there is a smoothie stand on the colorful tile courtyard, called Daniel's Coffee. There are also food stands along El Prado near Casa de Balboa.
For parking info, see below. For a map of the park, check out this nice map. 
Nearby, check out North Park, a neighborhood with cute craftman houses and two main areas with many coffee shops, cafes, and bars. And South Park, with houses with sweet gardens, and a gentille main strip with adorable Cafe Madeleine, woodsy Station Tavern, and a bookstore called The Book Catapult, with a great kids section and lots of art books.

Directions

The Organ Pavilion parking lot, which is free, is at the intersection of Pan American Rd East and President's Way, gives you good access to everything and holds a lot of spaces.
The Veterans Museum also has a large parking lot that is free and a fifteen walk to everything. It is almost guaranteed to have spaces.
The Alcazar parking lot is awesome as it's right by the Museum of Us in the main square, but it's often full unless you come early.
Spreckels Organ Pavilion Concerts, Sundays all year long 2pm, free. Mondays 7:30pm late June to Labor Day, free. 
Craft Cafe, outside Mingei Intl Museum, open 8:30am to 5pm daily. Lunch served till 3pm.

Click on map for interactive view