I am from
Colombia, and the last time I visited Santa Marta was about three years ago. Santa Marta is not as much yacht oriented as is Cartagena, yet it is still a great place to visit.
Santa Marta is very much oriented to tourists headed to the beach, as Santa Marta has many miles of beach. Santa Marta's beaches are much more extent and better looking than those of Cartagena. There are two main beach sections:
One is on the west side (the side closer to the airport) which is home to most of the resorts such as Irotama and Zuana, both very cool places to spend a week if you have the time and
income.
If you travel in opposite direction to the
airport (farther east I believe) you will find another popular tourist area called El Rodadero. This one doesn't have as much resorts, but has mainly condos, and some hotels that are less expensive than the ones described above. There are usually more people in this area in high season. Adjacent to El Rodadero is downtown Santamarta. There really is not much to do or sight see in downtown. Nothing compared to the compared to the infrastructure of downtown Cartagena.
However, there are several guided excursions and trips that leave from Santa Marta. My cousin was just in one this past summer, and it was great. You can usually find good rates for trips, but be careful not to be fooled. Do it in an agency, not from a beach vendor. My cousin went to Ciudad Perdida (the
Lost City), and hiked there for a week. This is basically a mountain that you climb in the jungle which leads you to the ruins of an ancient indian community. Along the way, you spend the night in indian villages who cook for you and rent hammocks for the night.The whole trip was under $250
Then he went to Parque Nacional Tayrona (tayrona national Park) which has some of the most beautiful beaches. There are a series of different beaches, and you can rent hammocks to spend the night. Some agencies offer the trip to Tayrona as a one day trip, where you go to tayrona either by boat or by bus, a one hour ride either way. Don't go in your own vessel, as the waves are very rough, and the bays are small and rocky.
Another trip you may consider is going to El Cabo the la Vela. This is an 8 hr. bus ride to the northeastern most part of the colombian coast in La Guajira, bordering
Venezuela. They have beautiful beaches, and the terrain is mainly desert. There are no hotels. Facilities are very primitive. If you go, there are several beach side huts that you can rent that have hammocks where you can sleep. However, I don't know if is navigable with a private yacht.
Another trip is to go to La Sierra Nevada which is a mountain covered by snow year round which is sometimes visible from the beach on a clear morning. This is home to Pico Colon, Colombia's highest peak, and there are excursions to hike the mountain. It is a unique mountain since you will be able to see the ocean if you hike it up far enough.
These are all great trips I would recommend. Put Tayrona as a must do, as it is a short distance form Santa Marta, and you can do it in one day.
Colombia is a beautiful and diverse country, and with the
current presidency and military control, it is very safe to travel inland.
I am now in th U.S., but some day too I will sail to Colombia.
Let me know know if you have any questions.