Can you top this?

Regular-gasoline prices as high as $4.19 per gallon were spotted in the Philadelphia area yesterday, according to consumer Web site PhillyGasPrices.com. Four stations - three in Conshohocken and one in Narberth - were advertising prices exceeding $4.

If you've seen higher prices for regular gas in the region, let us know.

Meanwhile, be advised that we're not alone: Prices this week have climbed above $4 in at least 15 cities, according to the Oil Price Information Service.

Based on OPIS numbers, if you want to put the most expensive gasoline among metro areas in the nation into your vehicle, you should head for a gas station in Bridgeport, Conn., or San Francisco.

For city residents tired of jumping the Delaware River to fill their gas tanks more cheaply, online gasoline directories offer guides and maps to the lowest-priced pumps.

Both PhillyGasPrices.com and MapQuest are frequently updated to reflect gas averages, as well as prices at specific stations. While MapQuest uses OPIS data, PhillyGas Prices.com relies on observant drivers to post their best gas finds.

Jason Toews, co-founder of GasBuddy.com and PhillyGas Prices.com, said that stations are competitive.

"If everybody goes to the cheap-priced stations, it forces the higher-priced stations to lower their prices," he said in a telephone interview. "That way you don't see large gaps between one station and stations at the other side of the scale."