Stay sunny, San Diego.

According to the latest edition of Hotels.com’s Hotel Price Index, the Southern California hot spot is the newest entrant among the top four cities for U.S. travelers. And overall, West Coast hotels saw a jump in their prices — with increases ranging from 5 percent to 13 percent — according to the study, which covers the first half of 2012.

The full study is available at the Hotel Price Index website.

Other findings:

Internationally, prices fell, with some key destinations — including Athens, Greece, and Pisa, Italy — taking a nosedive. If you’re heading from the U.S. to an international destination, expect to pay, on average, $171 per night.

The most expensive city? New York City, where a hotel room will put you back about $205 per night, according to the study. Honolulu ranks right behind at $204 per night.

Quickly rising in price? Charleston, S.C., which jumped from $100 per night to $152 per night between 2011 and 2012.

The best spot for a deal? Head southeast to find the five least-expensive cities for hotel stays. Columbia, S.C., is the cheapest at a mere $64 per night.

The most popular amenity? Free Wi-Fi — which, at 38 percent, is more popular than free breakfast (25 percent) — unless you’re over 60, at which point breakfast (34 percent) and Wi-Fi (27 percent) flop.

How important is the cost of a destination to your conference-goers? And what amenities are must-haves on your list?