Pattaya is the closest place to Bangkok offering diving, just 145km away. It is a thriving tourist mecca that is more akin to the hustle & bustle of Bangkok than the image of deserted, palm fringed tropical beaches.
Dive facilities are good, with numerous dive shops in the area. It is a popular place to learn to dive and, with a few good wrecks in the area, a popular place to try wreck-diving. There are also many options for professionals looking to become instructors. All of the dive sites around Pattaya can be reached by way of day trips.
Pattaya has an airport with connecting flights to Bangkok, Phuket & Ko Samui. It is also only a short bus ride from Bangkok, 145km away and is linked by rail to the capital. There is also a regional airport in Pattaya.
Pattaya receives a huge volume of tourists and has a huge number of accommodation options, but not necessarily a huge variety. Most accommodation is budget to mid-range hotels and apartments, often in built up areas. Hat Jomtien, to the south, has more luxury options.
One major plus of Pattaya is its range of activities. Watersports are hugely popular, there are also golf courses & go karting tracks, plus no shortage of places to eat and drink.