Least sprawling cities

Based on your definition of urban environment, many medium-to-small towns in the Northeast fit the bill. For instance, Beacon, NY has hiking trails that start right at the edge of town, and lots of farmstands and orchards are a quick bike ride away. Burlington, VT may work as well, and is an actual city unlike Beacon, though there's a little bit of sprawl to the south and east. Boulder, CO would be a perennial nominee as well. Do you have a size minimum that you're considering? Places that are hemmed in naturally by water and hills are going to be less sprawling just by virtue of their geography.

I live in Berkeley, California. Although the Bay Area does sprawl from one city to the next, Berkeley itself is very, very walkable without a car, and it is very close to open space/wilderness. There's even a great deal of open space within the city (Tilden Park is a 2,000+ acre wilderness area with trails, mountain lions, etc, a 10 minute walk from my apartment). It's a relatively short drive to gorgeous places like Point Reyes and other places along the Pacific, redwood forests, and only a few hours to Yosemite.

I think Seattle definitely fits your criteria, though it is also ringed by suburban development in some directions. We live in the city center with no car and we're able to do 90% of our errands on foot or by bike. There are some wilder parks within the city (like Discovery Park) and the mountains are literally 30 minutes away. There are also beautiful urban beaches, if that's your thing. Despite the suburbs around the city, the highways leading to the mountains and forests are still picturesque. Having grown up in the Midwest, I think I understand what you mean about having to slog through boring sprawl before you can get to the pretty stuff, and there's very little of that here.

OK so I am going to be the one who tells you that you are wrong, Los Angeles is the correct answer. First off, less than 100,000 people barely counts as a city, which knocks off about 90% of the stuff on this list. I picked my neighborhood in north-central Los Angeles so that I could live without a car; I had my choice of about 8 different neighborhoods that all had these same amenities. Within a 20 min walk of my apartment I have everything I need to live (subway stop that gets me to 40% of the city and bus stop that accesses another 20% more; or I can buy clothes, shoes, food (24 hour grocery store, and a mexican/eastern european grocery store, and bodegas, and 100+ restaurants with 50+ cuisines), books, jewelry, farmer's market, go to a regular doctor/dentist/optometrist or receive 24 hour urgent care) and also walk 15 min the other direction and hike one of the 53 miles of trails in the 4,000 acre undeveloped Griffith Park. Or I can get in my car and drive for 30 min-one hour on a highway through neighborhoods a lot like mine, and be in the Angeles National Forest (700,000 undeveloped acres), Topanga State Park (11,000 undeveloped acres), Santa Monica Mountains (40 square miles of undeveloped land), the Pacific Ocean (there are 7 state beaches and several city beaches), or one of the other 35 parks that I do not have space to name. It's popular to hate on LA as a Car City and you can live a Car Lifestyle, but more and more of us are coming here to choose the Car Free lifestyle and it's great!

Downtown Tucson's revitalization is going such that in a few years, depending on where one worked, one could survive without a car. There is a new full-service market going up downtown, and the Urban Streetcar project covers a fair amount of ground. It's a very bikeable city too. Nature-wise, there are mountains on three sides, a national park that the city splits in half (Saguaro), and there are two national recreation areas (Mount Lemmon and Sabino Canyon) that are readily accessible. Hiking abounds.

Santa Cruz and Santa Barbara are also walkable, compact, and near wilderness. I think they rank among the most compact cities in the U.S., but unlike bigger cities like New York (most compact), they have less in the way of suburban sprawl.

I was going to say Seattle. It gets sprawly to the north and south, but sprawl is nonexistent to the west because of Puget Sound (which you can cross in some short ferry trips to get to lovely islands and the Olympic Peninsula) and minimized to the east because of the mountains, which you can reach in 30-45 minutes depending on traffic and where you start. Seattle is getting more and more urban density every year, but manages to balance that nicely with lots of green spaces.

I have to say the Northwest is your best choice. I live in Denver now and it's definitely a great option, but nothing compares to Seattle all the way down to Ashland, Oregon. Even NorCal would be a good choice, but still, I'd totally do Seattle again or Portland. Check out Google Maps over Portland and notice Forest Park right there in the city. Good luck!

I'll add my pitch for Telluride. There's a slight chance it might've sprawled on one end, but the other three sides are contained by steep hills. It's small and fairly low density (most neighborhoods felt maybe 8 du/ac to me -- dense single family), but it has the grocery stores and other basics that you need. There's a well-defined main street. Not sure about say, a Home Depot, so you might find yourself making the occasional big shopping trip elsewhere. But otherwise, almost zero sprawl, stunning mountains, and a ski resort whose lift you can access on foot from town. The main downside is that it's probably really expensive. That, San Francisco, and Berkeley, are the best of the places I've ever been for an absence of sprawl and strip malls, and having easy access to surrounding natural areas. Oh, and Mendocino, CA! Almost zero sprawl. But the cultural life of the town intermingles with a few other towns that are more sprawling.