1. CSX parcel: A four-acre lot on the northwest corner of F and Second streets NE owned by CSX Corp. and under contract for sale to the development firm of Glen Urquhart and Associates. Zoning would allow high density mixed-use commercial development, including light industrial and hotel uses. City officials said Urquhart plans to build office and retail space on the site.

2. 717 Second St. NE: A new 18,000-square-foot office building built by Potomac Development Corp. Opened in late 1984 and has several tenants.

3. 220 I St. NE: Several townhouses rehabilitated into one office building by Potomac Development Corp. Opened in 1984, contains 29,000 square feet of mixed office and retail space and has one tenant, the Dole Foundation.

4. Site on H Street between Second and Third streets NE: A parking lot along H Street recently bought by Potomac Development Corp. and to be developed sometime in the next few years. The company says it will probably be mixed office and retail space.

5. Old Railway Express Building: A 1904-vintage brick warehouse with tile roof, bought by Potomac Development Corp. in December for $3 million. Potomac is planning to rehabilitate it into 120,000 square feet of mixed commercial and retail space, which they expected to be completed within next three or four years. In the future Potomac plans to expand the complex by building several hundred thousand square feet of office and retail space on the unused portion of the parcel.

6. Site inside the block between E and F and Second and Third streets NE: A commerically-zoned area within a block bounded on three sides by residential row houses that The Potomac Development Corp. has under contract to buy, with the idea of developing commercial or parking facilities on it later.

7. Future Greyhound bus station: A large site at the corner of K and First streets NE sold to the Greyhound Bus company for a new station. Construction has been delayed by a legal suit between the contractor and Greyhound, and it is unclear when the station will be built.

8. Kaiser Georgetown Clinic: A new building under construction on North Capitol Street north of K Street that will house a new Kaiser-Georgetown health clinic. It is expected to be completed in 1986.

9. Days Inn: A 300-room Days Inn, being built by developer Samuel Rose on a five-acre open lot at H and First streets NE. Construction will start next spring, with the opening of the hotel scheduled for summer of 1986.

10. 65 K ST. NE: A low-rise commercial building owned by Rose and adjacent to his large site. Rose said he plans to redevelop the site in the near future at a more intense use.

11. D.C. Vocational Education Facility: Construction site for a new D.C. Vocational Education Facility for the Handicapped at H Street and New Jersey Avenue. Expected to be completed in 1986.

12. Main City Post Office: Now that the Postal Service has announced that it will move the city postal operations out of the Main City Post Office building in 1988, the General Services Administration, the Architect of the Capitol and several private developers have voiced interest in using the historic building.

13. Post Office Expansion Site: Land owned by the D.C. government that the Postal Service had a contract on when it was considering expanding the facilities at the Main City Post Office. Now that the Post Office operation is going to be moved outside the area, the development rights to the land have reverted to the city. Considered by city officials as a prime site for private development to complement the Union Station complex.

14. Union Station: Being redeveloped into a train station and small retail and office mall with boutiques and restaurants. Expected to be completed by 1987. The city-financed parking garage behind the station is scheduled to be completed in 1986.

15. Federally owned lots: Three lots owned by the federal government which are slated to be developed in the future as office space for use by Congress. Control over what kind of building and when it would be built has been handed to the Union Station Redevelopment Corp., which may be ready to lease the land to developers later this year.

16. Georgetown University Law Center expansion: Georgetown University Law Center, at 600 New Jersey Ave., has bought most of the land in the parcel north of its present site and will start construction on an expansion of the law school next year. The new building, which will be roughly as large as their existing building, will cost about $20 million. Dennis Ransmeier, assistant dean for administration, said the school would also spend $7 million renovating its existing building. The expansion is expected to be completed in the summer of 1988.

17. Capitol Place: Three new office buildings built by Blum Frank & Kamins, which total 460,000 square feet of commercial space. Building one is open, and building two and three will be ready in September of 1985. A spokesman for the company said there are anchor tenants lined up for each building.

18. Sheraton Grand Hotel: A 272-room hotel at 500 New Jersey Ave. that opened two weeks ago. Developed by Blum Frank & Kamins.

19. Phoenix Park Hotel: A 84-room hotel at 525 North Capitol St., formerly known as the Commodore, and recently rehabilitated by the Carley Capital Group. It opened last winter.

20. 317 Massachusetts Ave. NE: A new 11,000-square-foot commercial building on the site of the former Bosley Dog and Cat Hospital being developed by the Stanton Square Development Corp. Kitty Kaupp, one of the three partners of the company, said that the company has also renovated three consecutive town houses on the other side of Massachusetts Avenue into office and retail space. Both developments will house new restaurants as well as offices.