shore excursions are very expensive but of course convenient.

Go to vallettawaterfront.com/…

There are buses into valletta and you can walk back to your ship along the harbour (don`t miss the Barakka Gardens with a grand view, including your ship)

You can also take a taxi tour which is much cheaper than a shore excursion

I saw this review on a recent cruise forum -

Malta: When planning the trip, I had viewed the half day in Malta as just something to do until we visited the more interesting ports in Italy. However, our experience in Malta was excellent. Just outside the dock we boarded a public bus that took us to the main bus stop near the main entrance to Valletta. We purchased "all-day" bus passes for about 4 Euros each. After reaching the bus circle, we took public bus route 84 to Medina, about a 30 minute drive out of town, with several stops along the way. (I believe that routes 81 and 82 could also be taken, although there seem to be no "express" routes.) The bus stops at Rabat, which is about a five minute walk from Medina. There is a bus stop between the Rabat stop and the entrance to Medina for the bus ride back to Valletta. The buses seem to run about every 30 minutes or so.

Medina is a medieval walled city, nicknamed "the Silent City." Very interesting, nice for photography, in and out in about an 75 minutes. Good for a side trip.

After arriving back at Valletta, we grabbed a quick soda at McDonald's (junk food fix) and then visited the St. John's Co-Cathedral. Malta was the headquarters of the Knights of the Order of St John of Jerusalem. If you like visiting historic buildings, this cathedral is a wonderful site. For us the most interesting features were the painting "The Beheading of St. John the Baptist" (unfortunately, but understandably, no photos or video were allowed to be taken), the main hall of the cathedral (with tombs of knights and grand masters literally build into the floor), and the bronze monstrance which supposedly contained the right arm of John the Baptist until the 1700s. The cost of entry was about 6 Euros each, which included a very good handheld audio guide.

We then proceeded down one of the main streets toward the fort at the end of the city, followed by a walk along the east side of the Valletta waterfront towards a large war memorial. From there we walked back to the ship (about a 20 minute walk) rather than walking back up to the bus circle to take a bus to the ship.