Last Monday we went to Balboa Park and went to the Air and Space Museum, the Automobile Museum, and the NAT (natural history museum).
After that we went to the Embarcadero and took a Hornblower boat cruise in the San Diego Harbor.
Tuesday we went to the Midway aircraft carrier museum
After all this I took the train back to San Ysidro and walked back across the border, took maybe 15 minutes, they don't seem to check anything, there was no passport check, I just walked in.
Bus back to Ensenada, great trip, extremely happy that my friends came to visit, we really had a good time.