The Sycamore Inn

Prime rib is the signature item and the dish most worth ordering on a first visit. The kitchen serves three cuts — an 8-ounce queen cut, a 12-ounce king cut, and a 16-ounce diamond Jim cut — slow-roasted in-house and served simply with au jus, horseradish cream, and the choice of baked potato or mashed potatoes plus seasonal vegetables. The roasting program produces consistent medium-rare doneness across the cuts with a substantial outer crust and tender pink interior. Prime rib is offered Wednesday through Sunday evenings until it sells out (the kitchen typically prepares enough for the expected covers; running out before close is uncommon but possible on busy weekend nights).

Beyond prime rib, the steak program includes a 16-ounce ribeye, a 14-ounce New York strip, a 10-ounce filet mignon, a 22-ounce Porterhouse, and smaller cuts for diners who want a steak but not a full steakhouse portion. Steaks are hand-cut in the kitchen and grilled over an open flame; the kitchen consistently executes ordered doneness levels with the kind of accuracy that less-careful steakhouses tend to miss. The beef is USDA Choice or better with several specialty Prime cuts available at higher prices.

Seafood, classic American sides, and a small range of non-beef entrees round out the menu. Pan-seared sea bass, broiled lobster tail, and a daily fresh fish special are the standard seafood options. Sides include lobster mac and cheese (a richer riff on the standard steakhouse macaroni), creamed spinach, sauteed mushrooms, and the standard baked potato presentations. Soups, salads, and a few appetizers round out the opener section. Desserts are classic American steakhouse — bread pudding, creme brulee, an apple-tart-of-the-week, and a notable affogato.

The main dining room is the 1939 Mission Revival space — a 90-seat room anchored by the substantial stone fireplace, exposed wood beams, white tablecloths, and lantern-style lighting. The walls are decorated with vintage Route 66 photographs, framed Sycamore Inn historical materials, and various memorabilia from the inn's roughly 180 years of operation. The aesthetic is warm dim ambiance even in mid-afternoon; evening service produces some of the most photogenic interior dining-room atmosphere in the Inland Empire.

The bar is a smaller intimate space adjacent to the main dining room — roughly 20 seats at the bar itself plus several small four-tops. The cocktail program is competent classic American — Manhattans, Old Fashioneds, Sazeracs, the standard steakhouse martini selection, and a small range of seasonal cocktails. The wine list emphasizes California producers with a deliberate concentration on Cucamonga Valley wineries (Galleano, Joseph Filippi, and several smaller boutique producers), which is unusual and worth taking advantage of as a wine-and-food pairing with the steakhouse menu. Bottle prices are reasonable for a historic destination restaurant.

The covered patio (in pleasant weather, March through November) provides about 30 additional seats with views of the parking lot, the sycamore grove, and Foothill Boulevard. The patio is genuinely pleasant for lunch and early-evening dining; less so for late-night dining when Foothill traffic produces some ambient noise. Patio dining requires a separate reservation request when booking and is generally accommodated.

Reservations are strongly recommended — the inn is small (about 120 total seats including the patio) and frequently books out 1 to 2 weeks in advance on weekend evenings, particularly during peak Route 66 tourism months (March through October) and around major holidays. Reservations can be made by phone or through the inn's website; the restaurant uses OpenTable for some bookings but direct phone reservations are the most reliable approach for special requests like patio seating or fireplace-side tables.

Dress code is casual to business-casual. The restaurant attracts a mix of customer types — Rancho Cucamonga locals in casual attire, Los Angeles diners dressed up for a special-occasion dinner, Route 66 road-trippers in travel-day clothes — and the management is genuinely welcoming across the range. Closed-toe shoes are appropriate; ties and jackets are not required but nicer attire is welcomed.

Hours are Tuesday through Sunday 11am to 10pm. Closed Mondays. Lunch service runs 11am to 2pm with a slightly lighter menu; dinner service starts at 5pm with the full menu including prime rib. The kitchen stops taking new orders at 9:30pm. The single best time to visit is a weekday evening (Tuesday through Thursday) at 6pm or 6:30pm — the dining room is at its best ambiance with sunset light through the windows, the kitchen is at peak quality, and the service pace is unhurried.

The Sycamore Inn is the natural dinner anchor for any Rancho Cucamonga heritage day. The classic plan: visit the 1937 Route 66 Service Station mid-morning (45 minutes), tour one or two Cucamonga Valley wineries in the afternoon (2-3 hours), and have a 6:30pm reservation at the Sycamore Inn for dinner. The pairing of three sites that span the area's stagecoach, wine-country, and Route 66 eras produces one of the most genuinely satisfying Inland Empire heritage experiences available.

For visitors based in Pasadena (20 miles west) or Los Angeles (40 miles west), Rancho Cucamonga and the Sycamore Inn are a comfortable evening drive along the historic Route 66 / Foothill Boulevard alignment. The drive itself is part of the experience — Foothill Boulevard retains substantial late-1930s and 1940s commercial architecture through the San Gabriel Valley cities, and traffic is generally manageable outside of rush hour.

For Route 66 road-trippers working through California's stretch of the highway, the Sycamore Inn is one of the essential mid-route dinners. The combination of the inn's pre-Route 66 history (Butterfield stagecoach, 1848 founding), Route 66-era architecture (1939 Mission Revival reconstruction), and continuous operation across roughly 180 years makes dinner at the Sycamore Inn genuinely different from other Route 66 restaurants — most surviving Mother Road eateries date from the 1920s through 1950s, and very few have any pre-highway history to draw on.