Maj. Jed. Hotchkiss, Confederate Military History, a library of Confederate States Military History: Volume 3, Virginia
Clement Anselm Evans, Ed.

[517] Subsequently the Confederate works were extended to the southwest of Petersburg for more than 10 miles, to beyond Hatcher's run, until Lee's line of defensive works, consisting of forts and redoubts connected by breastworks and strengthened by all means known to the art of war, extended for nearly 40 miles.

The Federal fortifications, commencing on the river road north of the James, in front of the Confederate lines, extended for four miles to the south, to Fort Brady, above Dutch gap; then were resumed, opposite the big bend of the James, and extended across the neck of the Bermuda Hundred peninsula, for nearly four miles, to the big bend of the Appomattox; then again resumed, upon the south side of that river and along its eastern side, and extended for over four miles, by redoubts and detached works, to the City Point railroad, on the bank of the Appomattox, and were thence prolonged, for 15 miles or more, around the front of Petersburg, to beyond Hatcher's run, frequently as double lines. South of these main defensive works, a line of formidable intrenchments protected the rear of the besieging army; while numerous forts, connected by heavy breastworks, extended across the City Point peninsula, making an enclosed camp for the base of supplies and the headquarters of the Federal army.

Grant ‘rested his men,’ as he had promised, with the vigorous use of intrenching tools, until near the end of June, constructing works far more formidable than those opposing him, and making such preparations as are only made when a great fortress is to be taken by protracted and regular siege operations. Within these well-fortified lines Grant collected more than 107,000 men, most of them veterans of the armies of the Potomac and of the James. To oppose these, Lee had, in his 40-mile line, for the defense of Richmond and Petersburg, some 54,000 men, the remaining veterans of the army of Northern Virginia, and of the department of North Carolina and Southern Virginia, Beauregard's army. Grant's supplies easily reached him by water, up the broad navigable James to City Point. Lee drew his, mainly from the South, by three railroads that met at Petersburg and were thence continued by single line to Richmond. The first Federal assault cut the roads leading to City Point and Norfolk.