Frontier Restaurant, late-night diner across from University of New Mexico

Directly across from the campus of the University of New Mexico and established in 1971, the vaguely barn-like Frontier Restaurant (2400 Central Ave. SE, 505-266-0550) is one of the state's great cheap-eats culinary treasures - a rambling collection of dining rooms hung with cowboy art and John Wayne portraits. Frontier had been open 24 hours for many years but currently serves food daily from 5 am until 1 am - plenty late to attract a curious mix of students, post-clubbing revelers, gays and lesbians, and regular folks from all walks of ABQ life. On weekdays, you'll often see students in here working or studying in one of the farther-back dining rooms.

Frontier specializes in low-frills, affordable New Mexican and American grub - there's often a long line of patrons, but it moves quickly. Service is fast and efficient. You order your food at the counter, wait for your number to appear on a flashing screen, and take it back to your table (basically, it's glorified cafeteria-style). There's no liquor license, but Frontier does serve a mean house-made lemonade as well as chai, cappuccino, and smoothies.

Best bets for breakfast are huevos rancheros and breakfast burritos, and definitely save room for one of the restaurant's trademark "sweet rolls" (basically Frontier's version of a cinnamon roll). For lunch and dinner, Frontier is known for its green-chile cheeseburger (the Fiesta burger, which you can have topped with red-chile, too, if you prefer), as well as carne adovada burritos, green-chile stew, beef tacos, and other New Mexico standards. There are better spots around town for authentic local food, but not many of them are this inexpensive or stay open this late. And as much as anything, dining at Frontier is about soaking up the quirky vibe and observing the often off-beat crowd.