Royal City Avenue (or just RCA as it is known by locals) is one of the biggest entertainment areas in Bangkok, but as visitors are concerned, probably the least know. RCA is a long road hosting a multitude of different types of bar and clubs. Very much a Thai scene, RCA is frequented by Bangkok's young scene, mainly university students letting off steam. Lots of variety of music depending on the bar you visit. Multi-million watt sound systems blast out Thai disco, house, R&B, and the usual American / Brit pop.
What's great about RCA is the wide range of places to eat and drink and the variety of themes in the clubs and restaurants. Catering for the local youth, it's not an overpriced venue. The new MRT connections have made RCA more accessible and so it is more often finding itself on the tourist map. Be warned though, if you are over 30 you'll feel old! Great place to visit if you are young and in Bangkok for an extended period, otherwise it's probably not going to be a high priority against some of the more central entertainment areas.
Details: Only a few of the clubs on RCA have entrance fees. This area is a designated 'Entertainment Zone' but the 01:00 curfew applies here like everywhere else.
How to get there: The quickest way to RCA is by MRT or BTS and a quick taxi ride the rest of the way. The nearest MRT is Pharam 9 station, and the nearest BTS Asok or Phrom Phong. From any of these stations the taxi fare should be no more than 50-60 Baht depending on traffic (it is a bit built up the area).
The following buses will get you close to RCA:
Bus number: 60
Air-conditioned bus number: 12